The Billboard Book of One-Hit Wonders, music journalist Wayne Jancik defines a one-hit wonder as "an act that has won a position on Billboard's national, pop, Top 40 just once." In his definition of an "act", Jancik distinguishes between a solo performer and any group he or she may have performed in (thus, for example, Roger Daltrey's "Without Your Love" is counted despite Daltrey's numerous hits as frontman for the Who), and a number of musicians appear multiple times, either with multiple bands or as a member of a band and as a solo artist.
1957