@article {PIE107,
	title = {Tracing the flow of organic matter from primary producers to filter feeders in Ria Formosa Lagoon, Southern Portugal},
	journal = {Estuaries},
	volume = {26},
	number = {4A},
	year = {2003},
	note = {Grad},
	pages = {846-856},
	keywords = {estuary, food web, LTER-PIE, stable isotope},
	doi = {10.1007/BF02803343},
	author = {Machas, R. and Santos, R. and Peterson, B.}
}
@mastersthesis {PIE18,
	title = {Analise isotopica da cadeia alimentar da Ria Formosa: Conribuicao relitiva dos produtores primaries},
	volume = {M.S.},
	year = {1999},
	note = {Grad},
	school = {University of Coimbra},
	type = {mastersthesis},
	address = {Coimbra, Portugal},
	keywords = {LTER-PIE, stable isotopes, carbon, nitrogen, sulfur, food web},
	author = {Machas, R.}
}
@article {PIE19,
	title = {Sources of organic matter in Ria Formosa revealed by stable isotope analysis},
	journal = {Acta Oecologica},
	volume = {20},
	year = {1999},
	note = {Grad},
	pages = {463-469},
	keywords = {carbon, estuary, food web, LTER-PIE, nitrogen, stable isotope},
	doi = {10.1016/S1146-609X(99)00122-8},
	author = {Machas, R. and Santos, R.}
}
