Kurtz, M.J. (16 juli 2005). ”Worldwide Use and Impact of the NASA Astrophysics Data System Digital Library”. The Journal of the American Society for Information Science and Technology "56": ss. 36. doi:10.1002/asi.20095. Bibcode: 2005JASIS..56...36K. (Preprint)
Kurtz, M.J. (16 juli 2005). ”Worldwide Use and Impact of the NASA Astrophysics Data System Digital Library”. The Journal of the American Society for Information Science and Technology "56": ss. 36. doi:10.1002/asi.20095. Bibcode: 2005JASIS..56...36K. (Preprint)
Kurtz, M.J. (16 juli 2005). ”Worldwide Use and Impact of the NASA Astrophysics Data System Digital Library”. The Journal of the American Society for Information Science and Technology "56": ss. 36. doi:10.1002/asi.20095. Bibcode: 2005JASIS..56...36K. (Preprint)