Duo for Violin & Viola in B flat,K 424 Duo for violin and viola in B flat major, KV 424 Duo for Violin & Viola in G,K 423 Duo for violin and viola in G major, K423 Duo for violin and viola in G major, KV 423 Duos for violin & viola;Divertimento in E flat. KV 563 Sonata for violin and piano in E flat Op.18 Duo for violin and violoncello Duos for violin & viola