@article{10_4064_sm169_1_2,
     author = {Peter \v{S}emrl},
     title = {Maps on idempotents},
     journal = {Studia Mathematica},
     pages = {21--44},
     publisher = {mathdoc},
     volume = {169},
     number = {1},
     year = {2005},
     doi = {10.4064/sm169-1-2},
     language = {en},
     url = {http://geodesic.mathdoc.fr/articles/10.4064/sm169-1-2/}
}