String Quartet No. 16 in E-flat major, K. 428/421b
The String Quartet No. 16 in E flat major, K. 428/421b, was composed by Wolfgang Amadeus Mozart in 1783. This is the third of the Haydn Quartets, a set of six string quartets he wrote during his first few years in Vienna and later dedicated to Joseph Haydn. The piece was probably first published in 1785.