@article{BASM_2003_2_a3,
     author = {Le Van Linh and A. P. Sadovskii},
     title = {The centre-focus problem for analytical systems of {Lienard} form in degenerate case},
     journal = {Buletinul Academiei de \c{S}tiin\c{t}e a Republicii Moldova. Matematica},
     pages = {37--50},
     publisher = {mathdoc},
     number = {2},
     year = {2003},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/BASM_2003_2_a3/}
}