The authors develop the fixed point theory on partial metric spaces and give some common fixed point theorems for four mappings satisfying the Ćirić type contraction condition. The main result (Theorem 2.1) generalizes the one proved quite recently in [I. Altun, F. Sola
and H. Simsek
, Topology Appl. 157, No. 18, 2778–2785 (2010); corrigendum ibid. 158, No. 13, 1738–1740 (2011; Zbl 1207.54052
)]. At the end of the paper some homotopy results are presented. Under suitable assumptions on a homotopy
(contractivity and continuity type conditions) the authors prove that
has a fixed point iff
has a fixed point.