@article{compref360,
   author = {Yudin,D and Goryashko,A},
   year = {1975},
   title = {Control problems and Complexity Theory II},
   journal = {Engineering Cybernetics (USSR)},
   volume = {13},
   pages = {1-13}
}

@article{compref359,
   author = {Yudin,D and Goryashko,A},
   year = {1974},
   title = {Control problems and Complexity Theory I},
   journal = {Engineering Cybernetics (USSR)},
   volume = {12},
   pages = {10-24}
}