Cortie, A. L. (1890). Father Perry, the Jesuit astronomer. Catholic Truth Society.
Lua i Stíl Chicago (17ú heag.)Cortie, A. L. Father Perry, the Jesuit Astronomer. London: Catholic Truth Society, 1890.
Lua MLA (8ú heag.)Cortie, A. L. Father Perry, the Jesuit Astronomer. Catholic Truth Society, 1890.
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