Yu, Dejian (CK) mapping and its fixed point. (Chinese. English summary) Zbl 0586.54052 J. Math., Wuhan Univ. 4, 303-310 (1984). MSC: 54H25 Fixed-point and coincidence theorems (topological aspects) Keywords:(CK)-mappings; Kannan mappings; mean nonexpansive mappings × Cite Format Result Cite Review PDF