A second mutation in the methylenetetrahydrofolate reductase gene and the risk of venous thrombotic disease - Franco, R. F.; Morelli, V.; Lourenço, D.; Maffei, F. H.; Tavella, M. H.; Piccinato, Carlos Eli; Thomazini, I. A.; Zago, Marco Antonio (British Journal of Haematology, 1999)