Lamar's duet with SZA samples Luther Vandross' 1982 hit "If This World Were Mine." The song was written by Marvin Gaye, who himself recorded it in 1967 as a duet with Tammi Terrell.

Kendrick Lamar and SZA's "Luther" leads the Billboard Hot 100 songs chart for an eighth total and consecutive week. The single, whose title celebrates late R&B legend Luther Vandross, who is ...