TY  - BOOK
AU  - Boltianskii, V. G.
AU  - Brown, Robert B.
TI  - ENVELOPES
U1  - 516.7 
PY  - 1964///
CY  - N. Y.
PB  - Macmillan
KW  - Envelopes (Geometry)
N1  - Translation Of Ogibaniushchaia; A Pergamon Press Book; Popular Lectures In Mathematics, V. 12
ER  -