Gribbin, M. d. J. (1997). Ruang & Waktu. Balai Pustaka.
Chicago Style (17th ed.) CitationGribbin, Mary dan John. Ruang & Waktu. Balai Pustaka, 1997.
MLA (8th ed.) CitationGribbin, Mary dan John. Ruang & Waktu. Balai Pustaka, 1997.
Warning: These citations may not always be 100% accurate.