Llano Brenes Prospect

BENNETT, EVAN, 1939, GOLD MINING IN COSTA RICA: ENG. MIN. J., V. 140, NO. 1, P. 56-58.HUTTL, J. B., 1942, A VISIT TO THE AGUACATE DISTRICT IN COSTA RICA: ENG. MIN. J., V. 143, NO. 11, P. 60-61.ROBERTS, R. J., AND IRVING, E. M., 1957, MINERAL DEPOSITS OF CENTRAL AMERICA, WITH A SECTION ON MANGANESE DEPOSITS OF PANAMA, BY F. S. SIMONS: U.S. GEOLOGICAL SURVEY BULLETIN 1034, 105 P.U.S. GEOLOGICAL SURVEY, DIRECCION GENERAL DE GEOLOGIA, MINAS E HIDROCARBUROS, UNIVERSIDAD DE COSTA RICA, 1987, MINERAL RESOURCE ASSESSMENT OF THE REPUBLIC OF COSTA RICA: U.S. GEOLOGICAL SURVEY MISCELLANEOUS INVESTIGATION SERIES MAP I-1865, 75 P.ROBERTS AND IRVING (1957)