Excursion guide book for Guatemala, 1967 :
Annual meeting /
S. Bonis, editor.

APA Citation

Geological Society of America., Bonis, S. B. (1967). Excursion guide book for Guatemala, 1967: Annual meeting. Guatemala: Instituto Geográfico Nacional.

MLA Citation

Geological Society of America, and Samuel B Bonis. Excursion Guide Book for Guatemala, 1967: Annual Meeting. Guatemala: Instituto Geográfico Nacional, 1967.

Warning: These citations may not always be complete (especially for serials).