Gaya APA

SCIENCES, N, E, R, C, O, G. (1977). South Essex geological and geotechnical survey part 12: Summary . : Walter Jenn Ltd..

Gaya MLA

SCIENCES, NATURAL, ENVIRONMENT, RESEARCH, COUNCIL-INSTITUTE, OF, GEOLOGICAL. "South Essex geological and geotechnical survey part 12: Summary". : Walter Jenn Ltd., 1977. Buku.