BibTex format
@inproceedings{Isham:1996:11A/002,
author = {Isham, CJ},
doi = {11A/002},
pages = {A5--A9},
publisher = {IOP PUBLISHING LTD},
title = {The challenge of quantum gravity},
url = {http://dx.doi.org/10.1088/0264-9381/13/11A/002},
year = {1996}
}