Toshikazu Miyashita, Ichiro Yokota "3-graded decompositions of exceptional Lie algebras $\mathfrak{g}$ and group realizations of $\mathfrak{g}_{ev}, \mathfrak{g}_0$ and $\mathfrak{g}_{ed}$ Part II, $G = E_7$, Case 5," Journal of Mathematics of Kyoto University, J. Math. Kyoto Univ. 47(1), 121-128, (2007)