Map
Hidden Lake Forest Preserve [site survey, ecological reconstruction, ecosystems/ecological value, slope, hydrology, soils, minerals, cultural improvements, and neighboring land use]circa 1975
Forest Preserve District of DuPage County
Book
Gœa Heidelbergensis : oder, Mineralogische Beschreibung der Gegend von Heidelberg 1830 – 1831
Bronn, H. G. (Heinrich Georg), 1800-1862