@book {4065,
	title = {Discrete Mathematics: A) The Mathematics of Computer Science, B) Problems and Solutions},
	year = {2008},
	author = {Christos Bouras and Lefteris Kirousis and Paul Spirakis and George Voutsadakis}
}
@book {3151,
	title = {Introduction to graphs: Theory, problems and solutions},
	series = {Gutenberg},
	year = {1999},
	author = {Christos Bouras and Lefteris Kirousis and Paul Spirakis and G Stamatiou}
}
@book {3152,
	title = {Discrete Mathematics: Problems and Solutions},
	series = {Gutenberg},
	year = {1994},
	author = {Christos Bouras and Lefteris Kirousis and Paul Spirakis and G Voutsadakis}
}
@book {3153,
	title = {Discrete Mathematics},
	series = {Gutenberg},
	year = {1992},
	author = {Christos Bouras and Lefteris Kirousis and Paul Spirakis}
}
