Wolpers M. Struktur und Stabilitat silanmodifizierter Metalloberflachen / M.Wolpers, 1991. - 134 S. - Текст : непосредственный.
Sustaining tel: from innovation to learning and practice : 5th european conference on technology enhanced learning, EC-TEL 2010, Barcelona, Spain, September 28 - October 1, 2010: proceedings / eds. M. Wolpers [et al.], 2010 r=on-line. - Текст : электронный.