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\textbf{Greek mythology; Parentage of Orpheus and Linus}\\[1em]
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	decoration={markings, mark=at position .65 with {\arrow[scale=1.5,black]{latex} } }]
	\node (a1) {Apollo or Unknown};
    \node (a2) at ($(a1)+(-2cm,-2.75cm)$) {Calliope or Terspichore};
    \node (a3) [right = 2cm of a2] {Daughter of Pierus};
    \node (a4) at ($(a3)+(1cm,2cm)$) {Pierus};
    \node (a5) [above=.75cm of a4] {Magnes or Makedon};
    \node (a6) at ($(a5)+(-3cm,1.5cm)$) {Aeolus or Naiad};
    \node (a7) [right=of a6] {Zeus or Thyia};
    \node (a8) [right=of a7] {Other Gods};
    \node (a9) [left=3.5cm of a1] {Ares or Charops};
    \node (a10) [below=1.5cm of a9] {Oeagrus};
    \node (a11) at ($(a2)+(.5cm,-2cm)$) {Orpheus};
    \node (a12) [right=1.5cm of a11] {Linus};
    \node (a13) [right=of a3] {Poseidon \& Urania};
    \node (a14) [right=2.5cm of a12] {Amphimarus};
    \node (a15) at ($(a11)-(1cm,1.5cm)$) {Euridice};
    \node (a16) [right=3cm of a15] {Nymph or Apollo's daughter};
    \node (a17) [below=of a15] {Mousaios};
    \node (a18) [left=1.5cm of a17] {Antiophemos};

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