Stall, John Byron; Gottschalk, L.C.; Klingebiel, Albert A.; Sauer, E.L.; Melsted, S.W. (Illinois State Water Survey, 1951)
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Studies with two 3-cm radars and dense surface hail networks showed that the
areal extent of hail during a given precipitation period can be estimated in a study area
from the areal extent of the highest half-order ...