(a) The 2nd and 3d volumes of +J. Grimm's+ 'Deutsche Grammatik'
(reprinted, Berlin 1878. 1890) ar stil the fundamental helps on
word-formation.
(b) The section on word-formation in +v. d. Gabelentz+ and +Löbe's+
'Grammatik', pp. 108-135.
(c) From a comparativ point of view: +Fr. Kluge+, 'Nominale
stammbildungslehre der altgermanischen dialekte'. Halle 1886.--See also
Brugmann, II, the sections concerning Gothic.