BP Rynne - Differential and Integral Equations, 2001 - projecteuclid.org
Lu= au+− bu−+ λu+ h,(2) where u±(x)= max {±u (x), 0} for x∈[0, π], and λ is a real parameter.
Values of λ for which (2)(with h= 0) has a nontrivial solution u will be called half-eigenvalues …