@book{503882,
	author = {Bajnok, Bela,},
	title = {An invitation to abstract mathematics /},
	publisher = {Springer,},
	year = {c2013},
	series = {Undergraduate texts in mathematics,},
	address = {New York, NY :},
	url = {https://link.springer.com/10.1007/978-1-4614-6636-9}
}