@booklet {6823,
	title = {SOUSA, M.P. de 1920. Contribution a l{\textquoteright}etude lithologique de l{\textquoteright}interieur de l{\textquoteright}Angola. Comptes Rendus Hebdomadaires des Seances de l{\textquoteright}Academie des Sciences, Paris, 170: 238-40.SOUSA, M.P. de 1921. Sur quelques roches remarquables de l{\textquoteright}Angola. Comptes Rendus },
	year = {1920},
	note = {SOUSA, M.P. de 1920. Contribution a l{\textquoteright}{\'e}tude lithologique de l{\textquoteright}int{\'e}rieur de l{\textquoteright}Angola. Comptes Rendus Hebdomadaires des S{\'e}ances de l{\textquoteright}Acad{\'e}mie des Sciences, Paris, 170: 238-40.SOUSA, M.P. de 1921. Sur quelques roches remarquables de l{\textquoteright}Angola. Comptes Rendus Hebdomadaires des S{\'e}ances de l{\textquoteright}Acad{\'e}mie des Sciences, Paris, 173: 777-80.}
}
@booklet {7271,
	title = {YOUNG, R.B. 1920. The rocks of a portion of Portuguese East Africa. Transactions of the Geological Society of South Africa, 23: 98-113.},
	year = {1920},
	note = {YOUNG, R.B. 1920. The rocks of a portion of Portuguese East Africa. Transactions of the Geological Society of South Africa, 23: 98-113.}
}
