@article {5499,
	title = {Scaling Descriptors for Language Proficiency Scales},
	journal = {Language Testing},
	volume = {15 (2)},
	year = {1998},
	pages = {217-262},
	keywords = {descriptors, language, proficiency, scales},
	url = {http://ltj.sagepub.com/content/15/2/217},
	author = {North, B. and Schneider, G.}
}
