Depth from defocus by changing camera aperture: a spatial domain approach. - Gopal Surya; Murali Subbarao (CVPR, 1993)

Depth from defocus: A spatial domain approach. - Murali Subbarao; Gopal Surya (Int. J. Comput. Vis., 1994)

Focused image recovery from two defocused images recorded with different camera settings. - Murali Subbarao; Tse-Chung Wei; Gopal Surya (IEEE Trans. Image Process., 1995)