diff -r 77e093529691 -r aa02c3117e2c src/pyams_gis.egg-info/requires.txt
--- a/src/pyams_gis.egg-info/requires.txt	Wed Jan 10 12:44:32 2018 +0100
+++ b/src/pyams_gis.egg-info/requires.txt	Sun Jan 14 12:51:31 2018 +0100
@@ -8,7 +8,7 @@
 pyams_viewlet
 pyams_zmi
 pyramid
-z3c.form
+z3c.form>=3.6
 zope.component
 zope.interface
 zope.schema