TY  - GEN
AU  - Annakkage ,  H.K.D.A.T.N.
AU  - jayasinghearachchi , D.A
TI  - Physices diffraction
U1  - 535.42 
PY  - 1989///
CY  - Nugegoda
PB  - Opean University
KW  - Physics
ER  -