1. A.V. Balakrishnan, "Boundary control of parabolic equations: L-Q-R theory", in Theory of nonlinear operators, Proc. Fifth Intern. Summer School, Berlin, Academie-Verlag, 1977.
2. G. Da Prato, "Regularity results of a convolution stochastic integral and applications to parabolic stochastic equations in a Hilbert space", Conf. Sem. Mat. Università di Bari, n.182, 1982.
3. G. Da Prato, "Some results on linear stochastic evolution equations in Hilbert spaces by the semigroups method", Stochastic Anal. Appl. 1, 57–88 (1983).
4. G. Da Prato, "Direct solution of a Riccati equation arising in stochastic control theory", Appl. Math. Optimiz. 11 (1984).
5. G. Da Prato, A. Ichikawa, "Stability and quadratic control for linear stochastic equations with unbounded coefficients", preprint, Scuola Normale Superiore, Pisa, May 1984.