Proposition: Prop. 11.16: Common Sections of Parallel Planes with other Plane are Parallel
Euclid's Formulation
If two parallel planes are cut by some plane then their common sections are parallel.
 For let the two parallel planes $AB$ and $CD$ have been cut by the plane $EFGH$.
 And let $EF$ and $GH$ be their common sections.
 I say that $EF$ is parallel to $GH$.
Modern Formulation
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Table of Contents
Proofs: 1
Mentioned in:
Proofs: 1 2
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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