@book{25783,
	author = {Emerson, R.A.},
	title = {A preliminary survey of the milpa system of maize culture as practiced by the Maya indiand of the Northern part of the Yucatan Peninsula},
	url = {https://drive.google.com/file/d/118Fu6DP2nfT9F7x2-3nZoh0r0P0qQEow/view?usp=drivesdk}
}