1. Efficiency of standard Army water purification equipment and of diatomite filters in removing cysts of Endamoeba histolytica from water: for official action Author(s): United States. Army. Engineer Board. Water Supply Equipment Branch, author.National Institute of Health (U.S.), author. Publication: Fort Belvoir, Virginia : Technical Staff, The Engineer Board, Corps of Engineers, U.S. Army, 3 July 1944 Subject(s): Military HygieneWater Purification -- instrumentationWater Purification -- standardsWater Supply -- standardsWater Pollution -- prevention & controlEndamoeba histolytica -- parasitologyUnited States