UMAT for sand hypoplasticity

"[email protected] [Abaqus]" <[email protected]> 09 May 2019 05:57:58 -0700

Newsgroups	gmane.comp.mathematics.abaqus.user
Message-ID	<[email protected]>

Dear all. 

 I was wondering if anyone uses the UMAT hypoplasticity subroutine by Masin, I need help with parameter No.(16).
 Thanks in advance.
 Aysar