@booklet {4480,
	title = {ECKEL, E.B., MILTON, C. and SULSONA, P.T. 1959. Geology and mineral resources of Paraguay - a reconnaissance. Professional Paper, United States Geological Survey, 327: 1-110.},
	year = {1959},
	note = {ECKEL, E.B., MILTON, C. and SULSONA, P.T. 1959. Geology and mineral resources of Paraguay - a reconnaissance. Professional Paper, United States Geological Survey, 327: 1-110.}
}
