de León, D. et al. 1971. REFRACTIVENESS OF PHYSA CUBENSIS (PFEIFFER) AND APPLEXA MARMORATA (GUILDING) TO FASCIOLA HEPATICA (L.). The Journal of Agriculture of the University of Puerto Rico. 55, 2 (Apr. 1971), 267–270. DOI:https://doi.org/10.46429/jaupr.v55i2.11055.