@article{ELMA_1967__22_140855,
     author = {P. L\"auchli},
     title = {Tangram - ein {Puzzle-Problem} f\"ur den {Computer.}},
     journal = {Elemente der Mathematik},
     pages = {73--85},
     publisher = {mathdoc},
     volume = {22},
     year = {1967},
     zbl = {0153.18802},
     url = {http://geodesic.mathdoc.fr/item/ELMA_1967__22_140855/}
}