- Royal Library of Belgium - KBR (Brussels): 1932
- Hendrik Conscience Heritage Library - EHC (Antwerp): 1932
De Rede, Orgaan van de Solidairen
- Hendrik Conscience Heritage Library - EHC (Antwerp): 1910
- Library of KU Leuven, special collection - KUL (Leuven): 1910
De Rede, Gewestelijke Vrijdenkersbond van Noord-België
- Hendrik Conscience Heritage Library - EHC (Antwerp): 1896-1900
- Institute of Social History - AMSAB-ISG (Ghent): 1895-1914
- Royal Library of Belgium - KBR (Brussels): 1898-1911
- Library of UGent, special collection (Ghent): 1895-1906
- Library of KU Leuven, special collection - KUL (Leuven): 1895-1899
De Rede, Landelijken Bond der Belgische Vrijdenkers
- Institute of Social History - AMSAB-ISG (Ghent): 1895
- Royal Library of Belgium - KBR (Brussels): 1895
- Archive and Documentationcentre for Flemish Nationalism - ADVN (Antwerp): 1914
- Institute of Social History - AMSAB-ISG (Ghent): 1911-1932
- Hendrik Conscience Heritage Library - EHC (Antwerp): 1911-1912; 1919-1920; 1932
- Library of KU Leuven, special collection - KUL (Leuven): 1911-1912
- Royal Library of Belgium - KBR (Brussels): 1921-1932
De Vrijdenker, Orgaan van de Solidairen (Antwerp)
- Royal Library of Belgium - KBR (Brussels): 1936 - 1938; 1939 - 1940
- Library of UGent, special collection (Ghent): 1937
- Institute of Social History - AMSAB-ISG (Ghent): 1934-1939
- Hendrik Conscience Heritage Library (Antwerp): s.d.
De Vrijdenker, Vrijdenkersunie (Antwerp)
- Hendrik Conscience Heritage Library (Antwerp): s.d.
- Institute of Social History - AMSAB-ISG (Ghent): 1946-1980
- Library of KU Leuven, special collection - KUL (Leuven): 1910
- Royal Library of Belgium - KBR (Brussels): 1923
L'Anticlérical Satirique Illustré
- Royal Library of Belgium - KBR (Brussels): 1902
- Library of KU Leuven, special collection - KUL (Leuven): 1902
- Library of UGent, special collection (Ghent): 1902
- Gallica, National Library of France - BNF (Paris, France): 1881
La Libre Pensée de Saint-Gilles
- Royal Library of Belgium - KBR (Brussels): 1937 [- ...]
- Royal Library of Belgium - KBR (Brussels): 1905-1965; 1919-1935; 1930
- Hendrik Conscience Heritage Library: 1914; 1970; 1973-1974
- Library of KU Leuven, special collection - KUL (Leuven): 1905; 1913; 1915
- Library of UGent, special collection (Ghent): 1905; 1910
- Institute of Social History - AMSAB-ISG (Ghent): 1929-1973; 1971-1977
- Université Libre de Bruxelles - ULB (Brussels): 1905-1913; 1966-1981
- Royal Library of Belgium - KBR (Brussels): 1895 -1899; 1900
- Hendrik Conscience Heritage Library (Antwerp): 1884; 1989-1893; 1894-1899; 1901-1904
- Library of UGent, special collection (Ghent): 1890; 1893; 1900-1901
- Université Libre de Bruxelles - ULB (Brussels): 1889-1924
- Université de Louvain - UCL: 1882
- Library of KU Leuven, special collection - KUL (Leuven): 1889-1892
- Institute of Social History - AMSAB-ISG (Ghent): 1896-1900
- Library of the Université Libre de Bruxelles - ULB (Brussels): 1861-1866
- Institute of Social History - AMSAB-ISG (Ghent): 1861-1896
- Royal Library of Belgium - KBR (Brussels): 1861-1896
- Royal Library of Belgium - KBR (Brussels): 1937
- Institute of Social History - AMSAB-ISG (Ghent): 1946-1972
- Archive and Museum of Literature - AML (Brussels): 1940
- Institut d'histoire ouvrière, économique et sociale - IHOES (Seraing): 1904
- Documentation and Research Centre on Religion - KADOC (Leuven): 1905
- Library of KU Leuven, special collection - KUL (Leuven): 1904
- Liberal Archives - Liberas (Ghent): 1904
- Library of UGent, special collection (Ghent): 1904-1905
- Archive of the city of Brussels - AVB-SAB (Brussels): 1904
- Royal Library of Belgium - KBR (Brussels): 1856-1858
- Royal Library of Belgium - KBR (Brussels): 1846-1868
- Archive of the city of Brussels - AVB-SAB (Brussels): 1865-1868
- Hendrik Conscience Heritage Library (Antwerp): 1865
- Library of KU Leuven, special collection - KUL (Leuven): 1864
- Library of UGent, special collection (Ghent): 1864
- Library of KU Leuven, special collection - KUL (Leuven): 1887; 1856; 1902
- Hendrik Conscience Heritage Library (Antwerp): 1887
- Library of UGent, special collection (Ghent): 1856
- Royal Library of Belgium - KBR (Brussels): 1922; 1940
- Library of the Université Libre de Bruxelles - ULB (Brussels): 1855-1865
- Library of UCLouvain - UCL (Louvain-la-Neuve): 1911-1912
- Hendrik Conscience Heritage Library (Antwerp): 1913