Industrie en vormgeving in Nederland 1850-1950, Amsterdam 1985, p. 69, 207-208, 223-229
Kunstnijverheid in Nederland 1880-1940, Eliëns/Groot/Leidelmeijer 1996, p. 217
Twee eeuwen tafelzilver : de Amsterdamse zilversmeden Helweg, 1753-1965 [2e dr.], Van Benthem 1996, p. 176, 203
Gero : zilver voor het volk, Van Egmond 2002, passim
Zeist, zilver, werken, Krekel-Aalberse 2004, p. 15-33 en passim
Designers in Nederland : een eeuw productvormgeving, De Rijk 2004, p. 148
Plaats/periode
ZeistZeist, 1910-1925, In 1910 Marius Johannes Gerritsen (1882-1954) who left his father´s company in 1909 to start his own silver factory, established (together with his brother in law and partner Julius ter Beek (1888-1967)) the Eerste Nederlandsche Fabriek van Nieuw-Zilverwerken van M.J. Gerritsen en Co.. The factory produced argentine products (´alpacca´ and silver-plated products). In 1917 the name Gero as a brand for alpacca-flatware was registered and in 1918 the trademark Gerofabriek was introduced. Marius Gerritsen left the company in 1922 and founded a new company called Gerrowé, later renamed as Sola. (A. Krekel-Aalberse, Zeist, zilver, werken, Zwolle 2004, p. 15-33)
ZeistZeist, 1925-1975, In 1925 the company name N.V. Eerste Nederlandsche Fabriek van Nieuwzilverwerken v/h firma M.J. Gerritsen en Co. (N.V. Gerofabriek) was altered into N.V. Gerofabriek Fabriek van Nieuwzilveren Werken; around 1930 the official name became Gerofabriek. In 1975 the factory in Zeist was shut down and the production was concentrated in Nieuw Weerdinge. In 1985 Gero was bought by Koninklijke Van Kempen & Begeer and moved its activities to the new premises in Zoetermeer.