In this papar we consider an important class of first order partial differential equations (or, holonomic systems). The notion of general Clairaut type equations is one of the generalized notions of classical Clairaut equations. We give a generic classification of holonomic systems of general Clairaut type as an application of the theory of complete Legendrian unfoldings.
"Holonomic systems of general Clairaut type." Hokkaido Math. J. 34 (1) 247 - 263, February 2005. https://doi.org/10.14492/hokmj/1285766207