East Front, Parthenon: Northern half. Measurements of Entablature &e. and upper and lower Drums of the Columns. Plate 7 ch. II, Sec. 2, by Francis Penrose, 1888.
An investigation of the principles of Athenian architecture: or the results of a recent survey conducted chiefly with reference to the optical refinements exhibited in the construction of the ancient buildings at Athens.
Francis Penrose, 1888
Source: https://digi.ub.uni-heidelberg.de/diglit/penrose1888
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