Necessary and sufficient conditions are given for almost all paths of a Gaussian process to be absolutely continuous (with derivative in $L_p$). Also sufficient conditions for almost sure path absolute continuity of second order processes are derived, slightly generalizing those previously known.
"On the Path Absolute Continuity of Second Order Processes." Ann. Probab. 3 (6) 1050 - 1054, December, 1975. https://doi.org/10.1214/aop/1176996233