7.5 minute series (topographic), [Puerto Rico]. 18066-A1-TM-020, Caguas quadrangle, Puerto Rico, 1964 mapped, edited, and published by the Geological Survey ; commonwealth of Puerto Rico, Department of Transportation and Public Works.
Reston, Va. : The Survey ; Denver, Colo. : For sale by the Survey ; San Juan, P.R. : Dept. of Transportation and Public Works, [19--]-