Advanced Linear Algebra
《Advanced Linear Algebra》 · 第 185-186 页 · Chapter 8「Eigenvalues and Eigenvectors」，Definition 条目 1)
1) A scalar $\lambda\in F$ is an eigenvalue (or characteristic value) of $\tau$ if there exists a nonzero vector $v\in V$ for which $\tau v=\lambda v$. In this case, $v$ is called an eigenvector (or characteristic vector) of $\tau$ associated with $\lambda$.