Messanae Universitas Studiorum: No conditions. Results ordered -Date Deposited. 2017-03-25T23:42:19ZEPrintshttp://cab.unime.it/images/sitelogo.pnghttp://cab.unime.it/mus/2012-10-05T11:10:10Z2012-10-05T11:10:10Zhttp://cab.unime.it/mus/id/eprint/995This item is in the repository with the URL: http://cab.unime.it/mus/id/eprint/9952012-10-05T11:10:10ZNull 2-type surfaces in minkowski space-time, IIIn the first part of this series [3], we prove that a space-lilce surface $M$ in the Minkowski space-time $E^4_1$ is of null 2-type with nonzero constant mean curvature if and only if $M$ is a helical cylinder of the first or the second kind in $E^4_1$. In this part, we completely classify null 2-type space-like surface in $E^4_1$ with light-like mean curvature vector. B.Y. ChenH. Song