HISTORY OF THE GUANO MINING INDUSTRY
Segment of mine track in Cueva Diamante
Segmento de vía en la mina en Cueva Diamante
Frank, Edward F. “History of the Guano Mining Industry, Isla de Mona, Puerto Rico.” Journal of Cave and Karst Studies 60(2)(1998): 121-125. Web. 28 Feb. 2013. <http://www.caves.org/pub/journal/PDF/V60/V60N2-Frank-History.pdf>
Used with permission / Usado con permiso