Del Prado, M. G. "The Mayon Volcano: A poem of grace and majesty". s.n.
芝加哥风格引文Del Prado, Mariano Goyena. "The Mayon Volcano: A Poem of Grace and Majesty". s.l: s.n.
MLA引文Del Prado, Mariano Goyena. "The Mayon Volcano: A Poem of Grace and Majesty". s.n.
警告：这些引文格式不一定是100％准确.