Building construction
United States Patent 2171540

Inventors:
Calkins, Raymond M.
Swank, James W.
Publication Date:
09/05/1939
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Assignee:
Calkins, Raymond M.
Swank, James W.
Primary Class:
52/377
Other Classes:
52/845
International Classes:
E04B2/60; E04C3/07; E04B2/58; E04C3/04