FACTA UNIVERSITATIS SERIES MATHEMATICS AND INFORMATICS, Vol. 14, 1999 Contents B. Dragović On Some Finite Sums with Factorials A. Stokolos On the Rate of Approximation Almost Everywhere by Steklov Means With Respect to Multidimensional Intervals M. Pikula and T. Marjanović The Regulation Independent of the Potential Symmetrical to the Center for Sturm'Liouville Operator With a Constant Delay J. Popenda and E. Schmeidel Asymptotically Periodic Solution of Some Linear Difference Equations O. Agratini On a Sequence of Linear and Positive Operators W. Themistoclakis Trigonometric Wavelet Interpolation in Besov Spaces A. Torgašev Dual Space of a Quaternion Hilbert Space V. Rakočević Apostol Spectrum and Generalizations: a Brief Survey M. C. De Bonis An Algorithm for the Evaluation of the Two-Dimensional Hilbert Transform With Non-standard Weight Functions P. P. Blaga An Approximate Formula for Multiple Integrals N. Kjurkchiev and M. S. Petković On the Divergent Properties of Two-sided SOR Weierstrass Method S. V. Pereverzev On the Sparse Representation of Operators for Solving Ill-Posed Problems S. G. Solodky Complexity for Some Classes of Equations of the Second Kind