\documentclass{amsart}
\usepackage{amsmath,amssymb,nopageno}
\usepackage[all]{xy}
\begin{document}
\begin{equation*}
\xymatrix@=1em{
  & &   & &   & &    & & & & \\
  & &   & &   & &    & & & &\\
  & &   & &   & &    & & & &\\
  & &   & & Z' \ar[rrddd]^f \ar[rruuu]& &    & & & &\\
  & &   & &   & &    & & & &\\
  & &   & &   & &    & & & &\\
  & & Y \ar[rruuu]^j \ar[rrd]^v & &   & & Y' \ar[rrddd]^g \ar[rru] & & & &\\
  & &   & & Z \ar[rru] \ar[rrrrdd] & &    & & & &\\
  & &   & &   & &    & & & & \\
X \ar[rruuu]^u \ar[rrrruu]_{v \circ u} & &   & &   & &    & &
    X' \ar[rrddd] \ar[rrd]^i & & \\
  & & & & & & & & & & \\
  & & & & & & & & & & \\
  & & & & & & & & & &
}
\end{equation*}
\end{document}

DescriptionAxiom TR4 (BBD).svg	A depiction of axiom TR4 of a triangulated category. This variant is a presentation due to Beilinson, Bernstein, and Deligne.
Date	13 January 2009
Source	Own work (Original text: I created this work entirely by myself.)
Author	Ryan Reich
Other versions	File:Octahedral diagram deligne.svg, File:Axiom TR4 (BBD).svg
SVG development InfoField	The SVG code is valid.   This diagram was created with an unknown SVG tool.

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