diff --git a/mural/utils.py b/mural/utils.py
index e1cf2bf..50680dc 100644
--- a/mural/utils.py
+++ b/mural/utils.py
@@ -8,15 +8,15 @@ def getSpaceUsers(user, post):
 	elif post._my_subclass == "categorypost":
 		space = post.get_space()
 
-		return User.objects.filter(Q(is_staff = True) | Q(coordinators__id = space) | Q(professors__category__id = space) | Q(subject_student__category__id = space)).exclude(id = user)
+		return User.objects.filter(Q(is_staff = True) | Q(coordinators__id = space) | Q(professors__category__id = space) | Q(subject_student__category__id = space)).exclude(id = user).distinct()
 	elif post._my_subclass == "subjectpost":
 		space = post.get_space()
 
 		if post.subjectpost.resource:
 			resource = post.subjectpost.resource
 
-			return User.objects.filter(Q(is_staff = True) | Q(professors__id = space) | Q(coordinators__subject_category__id = space) | Q(resource_students = resource) | Q(group_participants__resource_groups = resource) | (Q(subject_student__id = space) & Q(subject_student__topic_subject__resource_topic = resource) & Q(subject_student__topic_subject__resource_topic__all_students = True))).exclude(id = user)
+			return User.objects.filter(Q(is_staff = True) | Q(professors__id = space) | Q(coordinators__subject_category__id = space) | Q(resource_students = resource) | Q(group_participants__resource_groups = resource) | (Q(subject_student__id = space) & Q(subject_student__topic_subject__resource_topic = resource) & Q(subject_student__topic_subject__resource_topic__all_students = True))).exclude(id = user).distinct()
 		else:
-			return User.objects.filter(Q(is_staff = True) | Q(professors__id = space) | Q(coordinators__subject_category__id = space) | Q(subject_student__id = space)).exclude(id = user)
+			return User.objects.filter(Q(is_staff = True) | Q(professors__id = space) | Q(coordinators__subject_category__id = space) | Q(subject_student__id = space)).exclude(id = user).distinct()
 
 	return None
\ No newline at end of file
--
libgit2 0.21.2