TY  - BOOK
AU  - Green,M.
AU  - Lengo,R.
AU  - Randjbar-Daemi,S.
AU  - Sezgin,E.and
AU  - Strominger,A.
TI  - Superstrings '89. Proceedings of the Trieste Spring School, 3-14 April 1989
SN  - 9810201389
PY  - 1990///
CY  - Singapore
PB  - World Scientific
ER  -