A. Blömer, Die Erbförsterfamilie Nickel zu Gressenich, Mönchengladbach 1986, S. 110
__ | __|__ | Abraham KALS | __ | x1728 | | | |__|__ | Jakob KALS | __ | (1732-....)x1752 | | | | __|__ | | | | | Maria Gertrud GAUL | __ | x1728 | | | |__|__ |--Sara Aleida KALS | (1764-....)x1786 __ | | | __|__ | | | _____________________| __ | | | | | | |__|__ | | | Anna Maria FEUERBACH | __ x1752 | | | __|__ | | |_____________________| __ | | |__|__