 Day was the Games Editor for Chess Canada Magazine and wrote the tournament book for the 1972 Closed Canadian Championship.He wrote a booklet on The Big Clamp opening system and co-authored a 1982 book on the Grand Prix Sicilian line with English Grandmaster Julian Hodgson.He wrote a book about the life and games of the late Canadian International Master Bryon Nickoloff (1956–2004), a close friend, published in 2007 by Chess'n Math Association.