@book{175815,
	author = {Wan Muhamad Amir Wan Ahmad, and Muhammad Shafiq Mohd Ibrahim,},
	title = {Categorical Data Analysis Using SPSS for Periodontology /},
	publisher = {Penerbit Universiti Sains Malaysia,},
	year = {[2019?]},
	address = {Pulau Pinang :},
	note = {Includes index}
}