Complex sentence: Between 1958 and 1963 Avedisian had six solo shows in New York galleries, including two at the Robert Elkon Gallery, where he continued to show almost every year until 1975.
Split into simpler sentences: Between 1958 and 1963 Avedisian had six solo shows in New York galleries, including two at the Robert Elkon Gallery. He continued to show at the Elkon Gallery almost every year until 1975.