A study of dislocations and inclusions in Yttrium Aluminum Garnet crystals with birefringence topography Shu Shiu-ying, Kuo Zhoun-zhung and Fong Duan J. Phys. Colloques, 41 C6 (1980) C6-186-C6-189 DOI: 10.1051/jphyscol:1980648