@book{250330,
	author = {Ahn, Chul.  and Heo, Moonseong,},
	title = {Sample size calculations for clustered and longitudinal outcomes in clinical research / },
	publisher = {CRC Press, },
	year = {2015.},
	series = {Chapman & Hall/CRC biostatistics series},
	address = {Boca Raton : }
}