Öpik, E. (1932). “Note on Stellar Perturbations of Nearly Parabolic Orbits”. Proceedings of the American Academy of Arts and Sciences67 (6): 169. doi:10.2307/20022899. ISSN0199-9818. JSTOR20022899.
Bailey, M. E.; Stagg, C. R. (1988). “Cratering constraints on the inner Oort cloud: steady-state models”. Monthly Notices of the Royal Astronomical Society235 (1): 1-32. doi:10.1093/mnras/235.1.1. ISSN0035-8711.
Weissman, Paul R.; Levison, Harold F. (1997). “Origin and Evolution of the Unusual Object 1996 PW: Asteroids from the Oort Cloud?”. The Astrophysical Journal488 (2): L133-L136. Bibcode: 1997ApJ...488L.133W. doi:10.1086/310940. ISSN0004-637X.
Oort, J. H. (1950). “The structure of the cloud of comets surrounding the Solar System and a hypothesis concerning its origin”. Bulletin of the Astronomical Institutes of the Netherlands11: 91-110. Bibcode: 1950BAN....11...91O. ISSN0365-8910.
Weissman, Paul R.; Levison, Harold F. (1997). “Origin and Evolution of the Unusual Object 1996 PW: Asteroids from the Oort Cloud?”. The Astrophysical Journal488 (2): L133-L136. Bibcode: 1997ApJ...488L.133W. doi:10.1086/310940. ISSN0004-637X.
Öpik, E. (1932). “Note on Stellar Perturbations of Nearly Parabolic Orbits”. Proceedings of the American Academy of Arts and Sciences67 (6): 169. doi:10.2307/20022899. ISSN0199-9818. JSTOR20022899.
Öpik, E. (1932). “Note on Stellar Perturbations of Nearly Parabolic Orbits”. Proceedings of the American Academy of Arts and Sciences67 (6): 169. doi:10.2307/20022899. ISSN0199-9818. JSTOR20022899.
Oort, J. H. (1950). “The structure of the cloud of comets surrounding the Solar System and a hypothesis concerning its origin”. Bulletin of the Astronomical Institutes of the Netherlands11: 91-110. Bibcode: 1950BAN....11...91O. ISSN0365-8910.
Bailey, M. E.; Stagg, C. R. (1988). “Cratering constraints on the inner Oort cloud: steady-state models”. Monthly Notices of the Royal Astronomical Society235 (1): 1-32. doi:10.1093/mnras/235.1.1. ISSN0035-8711.
Weissman, Paul R.; Levison, Harold F. (1997). “Origin and Evolution of the Unusual Object 1996 PW: Asteroids from the Oort Cloud?”. The Astrophysical Journal488 (2): L133-L136. Bibcode: 1997ApJ...488L.133W. doi:10.1086/310940. ISSN0004-637X.