@conference {67191,
	title = {Shift work and occupational accidents},
	booktitle = {20th International Symposium on Shift work and Working Time },
	year = {2011},
	month = {28June},
	address = {Sweden},
	author = {Zakaria A Yehia and El Attar M Samir and Siha S Mona and Farahat A Sahar}
}
