  | P. Helbig. "Arguments against the flatness problem in classical cosmology: a review." European Physical Journal H. Historical Perspectives on Contemporary Physics, 46, no. 1 (December 2021): 10. doi:10.1140/epjh/s13129-021-00006-9  Peer Reviewed verified by ORBi |
 | P. Helbig. "Calculation of distances in cosmological models with small-scale inhomogeneities and their use in observational cosmology: a review." Open Journal of Astrophysics, 3 (01 January 2020): 1. doi:10.21105/astro.1912.12269 Peer reviewed |
 | P. Helbig. "The m-z relation for Type Ia supernovae: safety in numbers or safely without worry?." Monthly Notices of the Royal Astronomical Society, 453, no. 4 (01 November 2015): 3975-3979. doi:10.1093/mnras/stv1796 Peer Reviewed verified by ORBi |
 | I. W. A. Browne, P. N. Wilkinson, N. J. F. Jackson, S. T. Myers, C. D. Fassnacht, L. V. E. Koopmans, D. R. Marlow et al. "The Cosmic Lens All-Sky Survey - II. Gravitational lens candidate selection and follow-up." Monthly Notices of the Royal Astronomical Society, 341, no. 1 (01 May 2003): 13-32. doi:10.1046/j.1365-8711.2003.06257.x Peer reviewed |
 | R. Kayser, P. Helbig, and T. Schramm. "A general and practical method for calculating cosmological distances." Astronomy and Astrophysics, 318, no. 3 (01 February 1997): 680-686. Peer Reviewed verified by ORBi |
 | P. Helbig. "Correction to: Redshift drift and strong gravitational lensing." Monthly Notices of the Royal Astronomical Society, 528, no. 2 (23 January 2024): 1582-1582. doi:10.1093/mnras/stae125 Peer Reviewed verified by ORBi |
 | P. Helbig. "Increasing crescents." The Observatory : a Review of Astronomy, 143, no. 1294 (01 June 2023): 131. Editorial reviewed |
 | P. Helbig. "Redshift drift and strong gravitational lensing." Monthly Notices of the Royal Astronomical Society, 519, no. 2 (February 2023): 2769–2772. doi:10.1093/mnras/stac3623 Peer Reviewed verified by ORBi |
 | P. Helbig. "Conserved quantities in cosmology." Paper presented at 31st Texas Symposium on Relativistic Astrophysics, Prague, Czechia, 12 September 2022. Editorial reviewed |
 | P. Helbig. "Don't take it from me: literature overview of arguments against the flatness problem." Poster session presented at 31st Texas Symposium on Relativistic Astrophysics, Prague, Czechia, 12 September 2022. Editorial reviewed |
 | P. Helbig. "Received Wisdom." The Observatory : a Review of Astronomy, 142, no. 1289 (01 August 2022): 142–156. Peer reviewed |
 | P. Helbig. "Other losses." The Observatory : a Review of Astronomy, 142, no. 1288 (01 June 2022): 114–115. Editorial reviewed |
 | P. Helbig. "On the absence of flat star clusters." The Observatory : a Review of Astronomy, 142, no. 1286 (01 February 2022): 12–13. Editorial reviewed |
 | P. Helbig. "Conserved quantities in cosmology." In 2022 Cosmology: Proceedings of the 56th Rencontres de Moriondby É. Augé and J. Dumarchez, 333–334. France: ARISF, 2022. Editorial reviewed |
 | P. Helbig. "Arguments against the flatness problem." In 2022 Cosmology: Proceedings pf the 56th Rencontres de Moriondby É. Augé and J. Dumarchez, 331–332. 979-10-96879-16-8. ARISF, 2022. Editorial reviewed |
| P. Helbig. "Arguments against the flatness problem in classical cosmology: a review." European Physical Journal H. Historical Perspectives on Contemporary Physics, 46, no. 1 (December 2021): 10. doi:10.1140/epjh/s13129-021-00006-9 Peer Reviewed verified by ORBi |
 | P. Helbig. "Cosmological Distances: Calculation of distances in cosmological models with small-scale inhomogeneities and their use in observational cosmology." Unpublished doctoral thesis, ULiège - Université de Liège, 2021. Jury: Jury: C. Barbier (Promotor), M.-A. Dupret, M. Tytgat, J. Surdej, R. Stabell, and L. Delchambre. . |
 | P. Helbig. "Kapteyn in Leiden." The Observatory : a Review of Astronomy, 141, no. 1284 (01 October 2021): 247–248. Editorial reviewed |
 | P. Helbig. "Fifty Years of the Flatness Problem." Paper presented at Cosmology from Home, Auckland, New Zealand, 05 July 2021. |
 | P. Helbig. "Can’t get there from here? Curious logic in the famous paper by Einstein and de Sitter." The Observatory : a Review of Astronomy, 141, no. 1282 (01 June 2021): 117–121. Peer reviewed |
 | P. Helbig. "The Elephant in the Open-Access Room." The Observatory : a Review of Astronomy, 141, no. 1282 (01 June 2021): 133–136. Editorial reviewed |
 | P. Helbig. "Don’t Mention the War." The Observatory : a Review of Astronomy, 141, no. 1282 (01 June 2021): 136–137. Editorial reviewed |
 | P. Helbig. "Sonne und mond, or, the good, the bad, and the ugly: Comments on the debate between mond and acdm." The Observatory : a Review of Astronomy, 140, no. 1279 (01 December 2020): 225-247. Peer reviewed |
 | P. Helbig. "Whatever happened to the Dyer-Roeder distance?." The Observatory, 140, no. 1277 (01 August 2020): 128-144. Peer reviewed |
 | P. Helbig. "Otto Heckmann: Friend or Foe?." The Observatory : a Review of Astronomy, 140, no. 1276 (01 June 2020): 92-94. Peer reviewed |
 | P. Helbig. "Chess-playing armchair cosmologists." The Observatory, 140, no. 1276 (01 June 2020): 94-98. Peer reviewed |
 | P. Helbig. "The flatness problem and the age of the Universe." Monthly Notices of the Royal Astronomical Society, 495, no. 4 (24 April 2020): 3571–3575. doi:10.1093/mnras/staa1082 Peer Reviewed verified by ORBi |
| P. Helbig. "Calculation of distances in cosmological models with small-scale inhomogeneities and their use in observational cosmology: a review." Open Journal of Astrophysics, 3 (01 January 2020): 1. doi:10.21105/astro.1912.12269 Peer reviewed |
 | P. Helbig. "The flatness problem and the age of the Universe." Poster session presented at 30th Texas Symposium on Relativistic Astrophysics, Portsmouth, United Kingdom, December 2019. |
 | P. Helbig. "Further Discussion of the Speeds of Light, Gravitational Waves, and Gravity." The Observatory : a Review of Astronomy, 139, no. 1268 (01 February 2019): 5-7. Peer reviewed |
 | P. Helbig. "The Big Bang: who really first suggested it?." The Observatory : a Review of Astronomy, 138, no. 1267 (01 December 2018): 305-306. Peer reviewed |
 | P. Helbig. "Life, the Multiverse, and Fine-Tuning: Do Probabilities Matter?." Poster session presented at Cosmology 2018 in Dubrovnik, Dubrovnik, Croatia, October 2018. |
 | P. Helbig. "A formula for confusion." The Observatory : a Review of Astronomy, 138, no. 1262 (01 February 2018): 22-25. Peer reviewed |
 | P. Helbig and J. Overduin. "Which flatness problem does inflation solve?." Poster session presented at 29th Texas Symposium on Relativistic Astrophysics, Cape Town, South Africa, December 2017. |
The Cambridge Photographic Atlas of Galaxies. Cambridge, United Kingdom: Cambridge University Press, 2017. |
 | P. Helbig. "The magnitude-redshift relation for type Ia supernovae, locally inhomogeneous cosmological models, and the nature of dark matter." In 2016 Cosmology: Proceedings of the 51st RENCONTRES DE MORIONDedited by E. Augé,, J. Dumarchez, and J. Trân Thanh Vân, 171-174. ARISF, 2016. |
 | P. Helbig. "The m-z relation for type Ia supernovae, locally inhomogeneous cosmological models, and the nature of dark matter." In https://indico.cern.ch/event/336103/contributions/edited by M. Kunz, 336103/contributions/786798. Geneva, Switzerland: University of Geneva, 2015. |
| P. Helbig. "The m-z relation for Type Ia supernovae: safety in numbers or safely without worry?." Monthly Notices of the Royal Astronomical Society, 453, no. 4 (01 November 2015): 3975-3979. doi:10.1093/mnras/stv1796 Peer Reviewed verified by ORBi |
 | P. Helbig. "Cosmology and cosmogony." The Observatory : a Review of Astronomy, 135, no. 1247 (01 August 2015): 218-220. Peer reviewed |
 | P. Helbig. "The m-z relation for Type Ia supernovae, locally inhomogeneous cosmological models, and the nature of dark matter." Monthly Notices of the Royal Astronomical Society, 451, no. 2 (01 August 2015): 2097-2107. doi:10.1093/mnras/stv1074 Peer Reviewed verified by ORBi |
 | P. Helbig. "A classic problem concluded." The Observatory : a Review of Astronomy, 134, no. 1240 (01 June 2014): 138-139. Peer reviewed |
 | P. Helbig. "Reply to Mr. Osmaston concerning the nature of the redshift." The Observatory : a Review of Astronomy, 134, no. 1236 (01 April 2014): 76-76. Peer reviewed |
 | P. Helbig. "Is There a Flatness Problem in Classical Cosmology?." In Springer Proceedings in Physicsedited by J. Bičák and L. Tomáš, 355-361. Heidelberg, Germany: Springer, 2014. doi:10.1007/978-3-319-06761-2_50 |
 | P. Helbig. "Cosmic Confusion." The Observatory : a Review of Astronomy, 133, no. 1236 (01 October 2013): 294-295. Peer reviewed |
 | P. Helbig. "Why stop at 2/3?." The Observatory : a Review of Astronomy, 132, no. 1229 (01 August 2012): 267-267. Peer reviewed |
 | P. Helbig. "Which law is Hubble's law?." The Observatory : a Review of Astronomy, 132, no. 1228 (01 June 2012): 183-184. Peer reviewed |
 | P. Helbig. "Is there a flatness problem in classical cosmology?." Monthly Notices of the Royal Astronomical Society, 421, no. 1 (01 March 2012): 561-569. doi:10.1111/j.1365-2966.2011.20334.x Peer Reviewed verified by ORBi |
 | J. P. McKean, I. W. A. Browne, N. J. Jackson, C. D. Fassnacht, and P. Helbig. "The Cosmic Lens All-Sky Survey parent population - I. Sample selection and number counts." Monthly Notices of the Royal Astronomical Society, 377, no. 1 (01 May 2007): 430-440. doi:10.1111/j.1365-2966.2007.11618.x Peer Reviewed verified by ORBi |
 | P. Helbig. "Constraints in the λ0-Ω0 plane from gravitational lensing." In New Cosmological Data and the Values of the Fundamental Parametersby A. Wilkinson, edited by A. Lasenby, 245. San Francisco, United States: ASP, 2005. |
 | J. P. McKean, I. W. A. Browne, P. Helbig, N. J. F. Jackson, and P. N. Wilkinson. "The Redshift Distribution of Flat-Spectrum Radio Sources at Low Flux-Densities." In New Cosmological Data and the Values of the Fundamental Parametersedited by A. N. Lasenby and A. Wilkinson. San Francisco, United States: ASP, 2005. |
 | E. Zackrisson, N. Bergvall, T. Marquart, and P. Helbig. "Can microlensing explain the long-term optical variability of quasars?." Astronomy and Astrophysics, 408, no. 1 (01 September 2003): 17-25. doi:10.1051/0004-6361:20030895 Peer Reviewed verified by ORBi |
| I. W. A. Browne, P. N. Wilkinson, N. J. F. Jackson, S. T. Myers, C. D. Fassnacht, L. V. E. Koopmans, D. R. Marlow et al. "The Cosmic Lens All-Sky Survey - II. Gravitational lens candidate selection and follow-up." Monthly Notices of the Royal Astronomical Society, 341, no. 1 (01 May 2003): 13-32. doi:10.1046/j.1365-8711.2003.06257.x Peer reviewed |
 | K.-H. Chae, A. D. Biggs, R. D. Blandford, I. W. Browne, A. G. de Bruyn, C. D. Fassnacht, P. Helbig et al. "Constraints on Cosmological Parameters from the Analysis of the Cosmic Lens All Sky Survey Radio-Selected Gravitational Lens Statistics." Physical Review Letters, 89, no. 15 (01 October 2002): 151301. doi:10.1103/PhysRevLett.89.151301 Peer Reviewed verified by ORBi |
 | E. Zackrisson, N. Bergvall, and P. Helbig. "Constraining Dark Matter with the Long-Term Variability of Quasars." In Lighthouses of the Universe: The Most Luminous Celestial Objects and Their Use for Cosmologyby E. Churazov, edited by M. Gilfanov and R. Sunyeav, 550. Springer, 2002. doi:10.1007/10856495_87 |
 | P. Helbig. "The Lens-Redshift Test Revisited." In Cosmological Physics with Gravitational Lensingedited by J. Trân Thanh Vân, Y. Mellier, and M. Moniez, 279. Les Ulis, France: EDP Sciences, 2001. |
 | P. Helbig. "The Current Status of CLASS." In Cosmological Physics with Gravitational Lensingedited by J. Trân Thanh Vân, Y. Mellier, and M. Moniez, 261. Les Ulis, France: EDP Sciences, 2001. |
 | S. T. Myers, N. J. F. Jackson, I. W. A. Browne, A. G. de Bruyn, A. C. S. Readhead, P. N. Wilkinson, C. D. Fassnacht et al. "CLASS: Cosmic Lens All-Sky Survey." In Gravitational Lensing: Recent Progress and Future Goalsby T. G. Brainerd and C. S. Kochanek. San Francisco, United States - California: ASP, 2001. Editorial reviewed |
 | A. D. Biggs, I. W. A. Browne, P. N. Wilkinson, T. W. B. Muxlow, P. Helbig, L. V. E. Koopmans, and C. S. Kochanek. "B0218+357: Time Delays and New MERLIN/VLA 5 GHz Maps of the Einstein Ring." In Gravitational Lensing: Recent Progress and Future Goalsby T. G. Brainerd and C. S. Kochanek, 137-138. ASP, 2001. |
 | P. Helbig, J. F. Marcias-Perez, A. Wilkinson, R. Davies, and R. Quast. "λ0 and Ω0 from Lensing Statistics and Other Methods: Is There a Conflict?." In Gravitational Lensing: Recent Progress and Future Goalsedited by T. G. Brainerd and C. S. Kochanek, 145-146. San Francisco, United States: ASP, 2001. |
 | P. M. Phillips, M. A. Norbury, L. V. E. Koopmans, I. W. A. Browne, N. J. Jackson, P. N. Wilkinson, A. D. Biggs et al. "A new quadruple gravitational lens system: CLASS B0128+437." Monthly Notices of the Royal Astronomical Society, 319, no. 2 (01 December 2000): 7-L11. doi:10.1111/j.1365-8711.2000.04033.x Peer Reviewed verified by ORBi |
 | P. Helbig and R. J. Nemiroff. "Current Status of the Astrophysics Source Code Library." In Bulletin of the American Astronomical Society, 1600. 2000. |
 | L. V. E. Koopmans, A. G. de Bruyn, C. D. Fassnacht, D. R. Marlow, D. Rusin, R. D. Blandford, I. W. A. Browne et al. "CLASS B0827+525: `Dark lens' or binary radio-loud quasar?." Astronomy and Astrophysics, 361, no. 3 (01 September 2000): 815-822. Peer Reviewed verified by ORBi |
 | J. F. Macias-Perez, P. Helbig, R. Quast, A. Wilkinson, and R. Davies. "Gravitational lensing statistics with extragalactic surveys. IV. Joint constraints on lambda0 and Omega0 from gravitational lensing statistics and CMB anisotropies." Astronomy and Astrophysics, 353, no. 2 (01 January 2000): 419-426. Peer Reviewed verified by ORBi |
P. Helbig, R. D. Blandford, I. W. A. Browne, A. G. de Bruyn, C. D. Fassnacht, N. Jackson, L. V. E. Koopmans et al. "Measuring cosmological parameters with the JVAS and CLASS gravitational lens surveys." In Texas Symposium on Relativistic Astrophysics and Cosmologyby P. P., edited by E. Auborg, M. T., and P. J, 13. Amsterdam, Netherlands: Elsevier, 2000. |
 | P. Helbig. "Gravitational lensing statistics with extragalactic surveys. III. Joint constraints on lambda_ {0} and Omega_ {0} from lensing statistics and the m-z relation for type IA supernovae." Astronomy and Astrophysics, 350, no. 1 (01 October 1999): 1-8. Peer Reviewed verified by ORBi |
 | P. Helbig, D. R. Marlow, R. Quast, P. N. Wilkinson, I. W. A. Browne, and L. V. E. Koopmans. "Gravitational lensing statistics with extragalactic surveys . II. Analysis of the Jodrell Bank-VLA Astrometric Survey." Astronomy and Astrophysics. Supplement Series, 136, no. 2 (01 April 1999): 297-305. doi:10.1051/aas:1999467 Peer Reviewed verified by ORBi |
 | A. D. Biggs, I. W. A. Browne, P. Helbig, L. V. E. Koopmans, P. N. Wilkinson, and R. A. Perley. "Time delay for the gravitational lens system B0218+357." Monthly Notices of the Royal Astronomical Society, 304, no. 2 (01 April 1999): 349-358. doi:10.1046/j.1365-8711.1999.02309.x Peer reviewed |
 | R. Quast and P. Helbig. "Gravitational lensing statistics with extragalactic surveys. I. A lower limit on the cosmological constant." Astronomy and Astrophysics, 344, no. 3 (01 April 1999): 721-734. Peer Reviewed verified by ORBi |
A. Biggs, I. W. A. Browne, P. Helbig, N. J. Jackson, L. King, D. R. Marlow, A. McGuinness et al. "Cosmological Parameters from the CERES Project." In Cosmological Parameters and the Evolution of the Universeedited by K. Sato, 64. Dordrecht, Netherlands: Kluwer, 1999. |
 | P. Helbig. "The Deltatheta-z_s relation for gravitational lenses as a cosmological test." Monthly Notices of the Royal Astronomical Society, 298, no. 2 (01 August 1998): 395-398. doi:10.1046/j.1365-8711.1998.01692.x Peer Reviewed verified by ORBi |
 | N. Jackson, P. Helbig, I. W. A. Browne, and L. Koopmans. "Light on dark lenses." New Astronomy Reviews, 42, no. 2 (01 August 1998): 97-100. doi:10.1016/S1387-6473(98)00028-1 |
P. Helbig. "The Delta theta-z$_{s}$ Relation as a Cosmological Test." In Large Scale Structure: Tracks and Traces : Proceedings of the 12th Potsdam Cosmology Workshop : Potsdam, Germany, 15-19 September 1997edited by V. Müller, S. Gottlöber, J. P. Mücket, and J. Wambsganß, 395-398. World Scientific, 1998. |
D. R. Marlow, A. D. McGuinness, I. W. A. Browne, P. N. Wilkinson, and P. Helbig. "A Search for Large-Image-Separation Gravitational Lenses in the JVAS Radio Survey." In Large Scale Structure: Tracks and Traces : Proceedings of the 12th Potsdam Cosmology Workshop : Potsdam, Germany, 15-19 September 1997edited by V. Müller, S. Gottlöber, J. P. Mücket, and J. Wambsganß, 327-328. World Scientific, 1998. |
 | N. J. F. Jackson, P. Helbig, I. W. A. Browne, C. D. Fassnacht, L. V. E. Koopmans, D. R. Marlow, and P. N. Wilkinson. "Lensing galaxies: light or dark?." Astronomy and Astrophysics, 334, no. 2 (01 June 1998): 33-L36. Peer Reviewed verified by ORBi |
 | D. R. Marlow, P. N. Wilkinson, P. Helbig, I. W. A. Browne, N. Jackson, and I. Perez-Fournon. "Constraining the Value of the Cosmological Constant Using JVAS/CLASS Lensing Statistics." In Observational Cosmology with the New Radio Surveysedited by M. Bremer, N. Jackson, and I. Péréz-Fournon, 339-340. Astrophysics and Space Science Library, Volume 226. Dordrecht, Netherlands: Kluwer, 1998. doi:10.1007/978-94-011-5238-9_59 |
Golden lenses.Edited by P. Helbig and N. Jackson. Lower Withington, United Kingdom: self-published, 1997. Editorial reviewed |
 | P. Helbig. "Measuring the Hubble constant with lens time delays in inhomogeneous universes." In Golden Lenses, Proceedings of a workshop held 23-25 June, 1997 at Jodrell Bank. Online at <A href="http://www.astro.multivax.de:8001/ceres/workshop1/proceedings.html">http://www.astro.multivax.de:8001/ceres/workshop1/proceedings.html</A>, id.27edited by P. Helbig and N. Jackson. 1997. |
| R. Kayser, P. Helbig, and T. Schramm. "A general and practical method for calculating cosmological distances." Astronomy and Astrophysics, 318, no. 3 (01 February 1997): 680-686. Peer Reviewed verified by ORBi |
 | P. Helbig and R. Kayser. "Cosmological parameters and the redshift distribution of gravitational lenses." Astronomy and Astrophysics, 308, no. 2 (01 April 1996): 359-367. Peer Reviewed verified by ORBi |
 | P. Helbig, R. Kayser, and T. Schramm. "ANGSIZ: A general and practical method for calculating cosmological distances." 1996. |
P. Helbig. "Predicted Lens Redshifts and Magnitudes." In Astrophysical Applications of Gravitational Lensingedited by C. S. Kochanek and J. Hewitt, 21. Dordrecht, Netherlands: Kluwer, 1996. |
 | P. Helbig. "Cosmological Parameters and Gravitational Lensing Statistics." In Seventeeth Texas Symposium on Relativistic Astrophysics and Cosmologyedited by H. Böhringer, J. E. Trümper, and G. E. Morfill, 600. New York, United States: New York Academy of Sciences, 1995. doi:10.1111/j.1749-6632.1995.tb17617.x |
 | P. Helbig. "Bestimmung kosmologischer Parameter durch Rotverschiebungsstatistik von Gravitationslinsen." Unpublished master thesis, UH - Universität Hamburg, 1993. Jury: Jury: S. Refsdal (Promotor). . |
 | P. Helbig. "Determining Cosmological Parameters through Statistics of Redshifts of Lens Galaxies." In Gravitational Lenses in the Universe: Proceedings of the 31st Liège International Astrophysical Colloquiumby J. Surdej, D. Fraipont-Caro, E. Gosset, S. Refsdal, and M. Remy, 33-39. Liège, Belgium: ULg - Université de Liège, 1993. |
