Volume 60, Number 1, March 2015

  S T U D I A

                UNIVERSITATIS BABEŞ-BOLYAI

                               MATHEMATICA

Mohammad Zurigat, Application of the multi-step homotopy analysis

method to solve nonlinear differential algebraic equations . . . . . . . . . . . . . . . . . . . .3

Josef Dvorak, On products of self-small abelian groups . . . . . . . . . . . . . . . . . . . . . 13

Ulrich Albrecht, A-Whitehead groups . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19

Dorin Andrica and Oana Liliana Chender, Rodrigues formula

for the Cayley transform of groups SO(n) and SE(n) . . . . . . . . . . . . . . . . . . . . . . . . 31

George A. Anastassiou and Merve Kester, Quantitative uniform

approximation by generalized discrete singular operators . . . . . . . . . . . . . . . . . . . . . 39

Said Abbas, Mouffak Benchohra and Boualem Attou Slimani, Partial hyperbolic

implicit differential equations with variable times impulses . . . . . . . . . . . . . . . . . . . . 61

Loriana Andrei, Some differential superordination results using

a generalized Salagean operator and Ruscheweyh operator . . . . . . . . . . . . . . . . . . . . 75

Ioan A. Rus, Iterates of increasing linear operators, via Maia's fixed

point theorem . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 91

Anca Maria Oprea, Coincidence point and fixed point theorems

for rational contractions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 99

I.K. Argyros and S.K. Khattri, Improved error analysis of Newton's

method for a certain class of operators . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 109

Iulia Coroian, On some generalizations of Nadler's contraction

principle . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . 123

Erratum: Semilinear operator equations and systems with potential-type

nonlinearities, Angela Budescu, Stud. Univ. Babes-Bolyai Math.,

59(2014), No. 2, 199-212 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 135

Retraction notice: Exact discrete Morse functions on surfaces, Vasile Revnic,

Stud. Univ. Babes-Bolyai Math., 58(2013), No. 4, 469-476 . . .. . . . . . . . . . . . . . . . . .137

Book reviews . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 139