[666] Quadratic polynomials and quadratic forms

[667] Discrete one-dimensional quasi-periodic Schrödinger operators with pure point spectrum

[668] Inequalities for certain Fuchsian groups

[669] On bounded analytic functions and closure problems

[670] Subspaces and quotients of$l$_{$p$}$⊕l$_{2}and$X$_{$p$}