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Haagsma, C., H. Blom, P. L C M. van Riel, H. van't, B. Giesendorf, D. van Oppenraaij-Em..., and L. B A. van de Putte. Influence of Sulphasalazine, Methotrexate, and the Combination of Both On Plasma Homocysteine Concentrations in Patients With Rheumatoid Arthritis. 1999.

Haagsma, C., et al. Influence of Sulphasalazine, Methotrexate, and the Combination of Both On Plasma Homocysteine Concentrations in Patients With Rheumatoid Arthritis. 1999.