Proposition: Prop. 10.004: Greatest Common Measure of Three Commensurable Magnitudes
(Proposition 4 from Book 10 of Euclid's “Elements”)
To find the greatest common measure of three given commensurable magnitudes.
 Let $A$, $B$, $C$ be the three given commensurable magnitudes.
 So it is required to find the greatest common measure of $A$, $B$, $C$.
Modern Formulation
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Table of Contents
Proofs: 1 Corollaries: 1
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References
Adapted from (subject to copyright, with kind permission)
 Fitzpatrick, Richard: Euclid's "Elements of Geometry"
Adapted from CC BYSA 3.0 Sources:
 Prime.mover and others: "Pr∞fWiki", https://proofwiki.org/wiki/Main_Page, 2016