  In this paper, with a view to improve the g-monotonicity condition, we
introduce the notion of g-comparability of a mapping defined on an ordered set
and utilize the same to prove some existence and uniqueness results on
coincidence points for linear contraction without g-monotonicity in ordered
metric spaces. Our results extend some classical and well known results due to
Ran and Reurings (Proc. Amer. Math. Soc. 132(2004), no.5, 1435-1443), Nieto and
Rodriguez-Lopez (Acta Math. Sin. 23(2007), no.12, 2205-2212), Turinici
(Libertas Math. 31(2011), 49-55), Turinici (Math. Student 81(2012), no.1-4,
219-229) and Doric et al. (RACSAM 108(2014), no.2, 503-510) and similar others.
