Baer’s study on permafrost (facsimile 1843) with comments by Erki Tammiksaar, published by Lorenz King (2001). The original typescript of Baer s study has 218 pages, was ready for printing in the 1840's, but never published. The typescript was discovered in 2000 in the archives of the university library of Justus Liebig University Giessen, Germany. (Book cover)
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