Complex sentence: Devey's style was later developed by other architects such as R. N. Shaw and Charles Voysey, both of whom studied under him, and were to become be founder members of the Arts and Crafts movement a generation later.
Split into simpler sentences: Devey's style was later developed by other architects such as R. N. Shaw and Charles Voysey, who both studied under him. Both Shaw and Voysey were to be founder members of the Arts and Crafts movement a generation later.