@article{10_4064_fm_97_2_95_103,
     author = {Ernest P{\l}onka},
     title = {Symmetric words in nilpotent groups of class \ensuremath{\leq} 3},
     journal = {Fundamenta Mathematicae},
     pages = {95--103},
     publisher = {mathdoc},
     volume = {97},
     number = {2},
     year = {1977},
     doi = {10.4064/fm-97-2-95-103},
     language = {en},
     url = {http://geodesic.mathdoc.fr/articles/10.4064/fm-97-2-95-103/}
}