@article{DM_2006_18_1_a4,
     author = {S. S. Marchenkov},
     title = {On the structure of partially ordered sets of {Boolean} degrees},
     journal = {Diskretnaya Matematika},
     pages = {63--75},
     publisher = {mathdoc},
     volume = {18},
     number = {1},
     year = {2006},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DM_2006_18_1_a4/}
}