@article{paperid:1066359,
author = {Najafi, Hamed},
title = {Operator means and positivity of block operators},
journal = {Mathematische Zeitschrift},
year = {2018},
volume = {289},
month = {June},
issn = {0025-5874},
pages = {445--454},
			numpages = {9},
keywords = {Positive block matrix-Operator monotone function-Operator mean},
}