@article{10_4064_fm_120_3_193_204,
     author = {J. Dudek},
     title = {Varieties of idempotent commutative groupoids},
     journal = {Fundamenta Mathematicae},
     pages = {193--204},
     publisher = {mathdoc},
     volume = {120},
     number = {3},
     year = {1984},
     doi = {10.4064/fm-120-3-193-204},
     language = {en},
     url = {http://geodesic.mathdoc.fr/articles/10.4064/fm-120-3-193-204/}
}