Disco.Services.Interop.ActiveDirectory.ActiveDirectoryGroupCache.GetRecursiveGroups C# (CSharp) Method

        public IEnumerable<ADGroup> GetRecursiveGroups(IEnumerable<string> DistinguishedNames)
        {
            List<ADGroup> groups = new List<ADGroup>();

            foreach (var distinguishedName in DistinguishedNames)
                foreach (var group in GetGroupsRecursive(distinguishedName, new Stack<ADGroup>()))
                    if (!groups.Contains(group))
                    {
                        groups.Add(group);
                        yield return group;
                    }
        }
        public IEnumerable<ADGroup> GetRecursiveGroups(string DistinguishedName)