Astore, W. J. (1995). Observing God: Thomas Dick (1774-11857), evangelicalism and popular science in Victorian Britain and antebellum America. British Library Document Supply Centre.
Chicago-viite (17. p.)Astore, William Joseph. Observing God: Thomas Dick (1774-11857), Evangelicalism and Popular Science in Victorian Britain and Antebellum America. Boston Spa, United Kindom: British Library Document Supply Centre, 1995.
MLA-viite (8. p.)Astore, William Joseph. Observing God: Thomas Dick (1774-11857), Evangelicalism and Popular Science in Victorian Britain and Antebellum America. British Library Document Supply Centre, 1995.
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