George Markowsky
J. Math. Anal. Appl.
We show that the semilattice extension problem raised by Arbib and Manes in [2] is NP-hard, implying that no simple solution is likely to be forthcoming. © 1983 Birkhäuser Verlag.
George Markowsky
J. Math. Anal. Appl.
Guo-Jun Qi, Charu Aggarwal, et al.
IEEE TPAMI
Charles A Micchelli
Journal of Approximation Theory
Richard M. Karp, Raymond E. Miller
Journal of Computer and System Sciences