International Journal of Mathematical Education in Science and Technology (Internat. J. Math. Ed. Sci. Tech.) (20100101), 41, no.~2, 229-242. ISSN: 0020-739X (print).eISSN: 1464-5211.
Inverse Problems. An International Journal on the Theory and Practice of Inverse Problems, Inverse Methods and Computerized Inversion of Data (Inverse Problems) (20130101), 29, no.~3, 035003, 22~pp. ISSN: 0266-5611 (print).eISSN: 1361-6420.
Comptes Rendus de l'Académie des Sciences. Série I. Mathématique (C. R. Acad. Sci. Paris Sér. I Math.) (19900101), 310, no.~8, 647-652. ISSN: 0764-4442 (print).