APA Style

et.al., H, B, S. (1997). Indonesian Association of Geophysicist (HAGI): Geofisika . Jakarta: Indonesian Association of Geophysicist (HAGI).

MLA Style

et.al., Hardjo, Basuki, Soenandar,. "Indonesian Association of Geophysicist (HAGI): Geofisika". Jakarta: Indonesian Association of Geophysicist (HAGI), 1997. Text.