Two complementary approaches to the theory of heavy quarkonia are discussed.
The nonrelativistic potential models give amazingly accurate predictions, but
lack a theoretical justification. The expansion in powers of v/c is
theoretically very acceptable, but is not as good in giving numerical
predictions. The importance of combining these two approaches is stressed.Comment: Presented at QCD'96 Montpellier 4-12 June 1996 7 pages, no figures,
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