@article {37512,
	title = {Introgressive hybridization in Heteroptera : the example of Limnoporus St{\r a}l (Gerridae) species in western Canada},
	volume = {68},
	year = {1990},
	pages = {1770-1782},
	publisher = {Canadian Journal of Zoology},
	url = {http://article.pubs.nrc-cnrc.gc.ca/RPAS/RPViewDoc?_handler_=HandleInitialGet\&calyLang=eng\&journal=cjz\&volume=69\&articleFile=z91-399.pdf},
	author = {Spence, J. R.}
}
