Monge–Ampère Operator on Four Dimensional Almost Complex Manifolds

We define the Monge–Ampère operator (i∂∂¯u)2\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$${(i\partial {\bar{\partial }}u)^{2}}$$\end{document} for continuous J-plurisubharmonic functions on four dimensional almost complex manifolds.