The complete citations for the studies I mention are:
Dominican University (2010). The Dominican study: Public library summer reading programs close the reading gap.” Retrieved from http://www.dom.edu/academics/gslis/imls/ClosetheReadingGap/
Heyn, B. (1978). Summer Learning and the Effects of Schooling. New York: Academic Press Inc.
Kim, J. S., & Guryan, J. (2007). “The efficacy of a voluntary summer reading intervention on reading activities and reading achievement.” Journal of Educational Psychology 99, 505‐515.
McTague, B., & Abrams, B. (2011). “Access to books: A scaffolded program creates readers.” Reading Improvement, 48(1), 3‐13.