source: On his return to Genoa in 1916 he opened his studio and worked mainly as a portrait artist, later enlarging his repertoire to landscapes of his native Liguria, covering the entire region and later on even some neighbouring regions.
target: On his return to Genoa in 1916, he opened his studio.  He worked mainly as a portrait artist.  Later, he enlarged his repertoire to landscapes of his native Liguria.  It covered the entire region and later on even some neighboring regions.
references: On his return to Genoa in 1916, he opened his studio.  He worked mainly as a portrait artist.  Later, he enlarged his repertoire to landscapes of his native Liguria.  It covered the entire region and later on even some neighboring regions.