Perspectives: Biblical Themes in St. Francis' Song of Brother Sun
Among the prayers and teachings of St. Francis of Assisi which have survived, the "Song of Brother Sun" or the "Canticle of the Creatures" is among those which show both his genius and his simplicity.
Frizzell, Lawrence, "Perspectives: Biblical Themes in St. Francis' Song of Brother Sun" (1982). Department of Religion Publications. 106.