APA Style

Agency, I, A, E. (1991). String Theory and Quantum Gravity : Proceedings of the trieste spring school 23 April-1 Mei 1990 . Singapore: WORLD SCIENTIFIC.

MLA Style

Agency, International, Atomic, Energy. "String Theory and Quantum Gravity : Proceedings of the trieste spring school 23 April-1 Mei 1990". Singapore: WORLD SCIENTIFIC, 1991. Buku.