@article{VUU_2006_1_a14,
     author = {N. A. Vershinina},
     title = {The constructive model of the environment in activities planning system},
     journal = {Vestnik Udmurtskogo universiteta. Matematika, mehanika, kompʹ\^uternye nauki},
     pages = {169--180},
     year = {2006},
     number = {1},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/VUU_2006_1_a14/}
}