J. J. Koenen, b: -






^{J. H. Welcker}^{b. d.}



		^{Matthijs Koenen}^{b. d.}

	^{August Johan Koenen}^{b.1862 Soerabaija, IDN d.1907 's-Gravenhage, ZH, NLD}	^{Johanna Lautenslager}^{b.1843 Joure, FR, NLD d.1928 's-Gravenhage, ZH, NLD}

^{J. J. Koenen}^{b. d.}		^S Lamminga^{b. d.}

	^{Jeltje Lamminga}^{b. d.}	^F Beitschat^{b. d.1902 Oosterbeek, GE, NLD}