Blankenship, Gilmer L., Baras, John S., "On the Conditional Density Equation in Nonlinear Filtering Problems", 1979 IEEE International Symposium on Information Theory, p. 97, Grignano, Italy, June 1979
Baras, John S., "Quantum Filtering with Counting Measurements", 1979 IEEE International Symposium on Information Theory, pp.1- 8, Grignano, Italy, June 1979
