Wikidata project: d:Wikidata:WikiProject sum of all paintings/Hofstede de Groot
Commons project: c:Category:Catalogs by Cornelis Hofstede de Groot
Wikipedia project: (each of these paintings is notable enough for an article and thanks to Hofstede de Groot, many have PD text available to generate one): User:Jane023/List of paintings catalogued by Hofstede de Groot

Catalogues Raisonné

Lists of paintings by painter by catalogue volume (German date, followed in parentheses by the English date):

• Band 1 1907 (Volume 1 1908) : Jan Steen, Gabriel Metsu, Gerard Dou, Pieter de Hooch, Carel Fabritius, Johannes Vermeer of Delft
• Band 2 1908 (Volume 2 1909) : Aelbert Cuyp, Philips Wouwerman
• Band 3 1910 (Volume 3 1910) : Frans Hals, Adriaen van Ostade, Isaac van Ostade, Adriaen Brouwer
• Band 4 1911 (Volume 4 1912) : Jacob van Ruysdael, Meindert Hobbema, Adriaen van de Velde, Paulus Potter
• Band 5 1912 (Volume 5 1913) : Gerard ter Borch, Caspar Netscher, Godfried Schalcken, Pieter van Slingeland, Eglon Hendrik van der Neer
• Band 6 1914 (Volume 6 1916) : Rembrandt, Nicolaes Maes
• Band 7 1918 (Volume 7 1923) : Willem van de Velde, Johannes van de Capelle, Ludolf Bakhuyzen, Aert van der Neer
• Band 8 1923 (Volume 8 1927) : Jan van Goyen, Jan van der Heyden, Johannes Wijnants
• Band 9 1926 (?) : Johannes Hackaert, Nicolaes Berchem, Karel du Jardin, Jan Both, Adam Pijnacker
• Band 10 1928 (?) : Frans van Mieris, Willem van Mieris, Adriaen van der Werff, Rachel Ruysch, Jan van Huysum