Two of country music's most prolific artists are featured in new career retrospectives released Tuesday (Aug. 1). The Essential Ronnie Milsap (RCA) collects 40 of the singer's biggest hits from 1975 to 1990. In addition, Buck Owens' 21 #1 Hits: The Ultimate Collection offers all of his chart-topping hits, from 1963's "Act Naturally" and "Love's Gonna Live Here" to 1988's duet with Dwight Yoakam, "Streets of Bakersfield."