Delta 'ANTPOT.14 C', sigma 'ANTPOT.13 C' and c in ventory differences between forest and pasture in soils of eastern amazonia - Camargo, Plinio Barbosa de; Trumbore, S E; Davidson, E A; Nepstad, D C; Martinelli, Luiz Antonio (Eos. Transactions. American Geophysical Union, 1993)