TY  - BOOK
AU  - J G CROWTHER
TI  - DISCOVERIES AND INVEN TION OF THE 20TH CENTURY
U1  - GN608.7C459D 
PY  - 1966///
CY  - LONDON
PB  - ROUTLEDGE AND KEGAN PAUL
KW  - DISCOVERIES AND INVEN TION OF THE 20TH CENTURY
ER  -