Young, S. R., Francis, P. W., Barclay, J., Cassadevall, T., Gardner, C., Daroux, B., Davies, M., Delmelle, P., Norton, G., Maciejweski, A., Oppenheimer, C. M., Stix, J., & Watson, J. (1998). Monitoring sulphur dioxide emission at the Soufrière Hills volcano: implications for changes in eruptive conditions. Geophysical Research Letters, 25(19), 3681-3684. https://doi.org/10.1029/98GL01406 (Original work published 1998)