We describe a method to reduce partial differential equations of
Monge-Amp\`ere type in 4 variables to complex partial differential equations in
2 variables. To illustrate this method, we construct explicit holomorphic
solutions of the special lagrangian equation, the real Monge-Amp\`ere equations
and the Plebanski equations.Comment: 16 pages, 5 tables To appear in Journal of Geometry and Physic