@article{ZNSL_2005_321_a9,
     author = {N. Kehayopulu and I. S. Ponizovskii and K.-P. Shum},
     title = {Retract extensions of ordered sets},
     journal = {Zapiski Nauchnykh Seminarov POMI},
     pages = {205--212},
     publisher = {mathdoc},
     volume = {321},
     year = {2005},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/ZNSL_2005_321_a9/}
}