Hoffman, I., Peene, I., Union, A., Meheus, L., Huizinga, T., Cebecauer, L., Isenberg, D., De Bosschere, K., Hulstaert, F., Veys, E., & De Keyser, F. (2004). False positivity of rheumatoid factor and antibodies to citrullinated peptides in systemic lupus erythematosus. Arthritis Research & Therapy, 6, S6. https://doi.org/10.1186/ar1058 (Original work published 2004)