Erratum: Characterization of eigenvalues by use of orthonormality‐constrained variation methods

Various kinds of methods are presented for performing variational characterization of eigenvalues of a self‐adjoint operator F bounded from below. The methods are derived from construction of ket vectors under the orthogonality and normality constraints through the process of variation. Application of the methods to the expectation value of the operator leads to variational equations, in each of these equations an extremum condition yielding an eigenvalue equation.