المؤلفون: KINARD, F. W., AULL, J. C., ULMER, R. E.

المصدر: Nature ; volume 184, issue 4700, page 1721-1721 ; ISSN 0028-0836 1476-4687

الاتاحة: http://dx.doi.org/10.1038/1841721a0
http://www.nature.com/articles/1841721a0
http://www.nature.com/articles/1841721a0.pdf