@misc {IOPORT.03794823,
    author       = {Kotarski, Wieslaw and Kowalewski, Adam},
    title        = {On application of conical approximations to an optimal control problem for parabolic systems.},
    howpublished = {Pr. Nauk. Uniw. \'Sl\c{a}sk. Katowicach 420, Pr. Mat. 11, 12-20 (1981).},
    year         = {1981},
    identifier   = {03794823},
}