Carlton C. Curtis
1907 · Fine
€50
Thompson, D'Arcy Wentworth
1931 · Fine
€35
J. Arthur Thomson
1909 · Fine
€45
Alfred Russel Wallace
1935 · Fine
€35
Arthur van Schendel
1921 · Fine · NL
€35
Nicolass Muller
1915 · Fine · NL
€35
F. Matthias Alexander
1935 · Fine
€35
H. Newell Martin
1903 · Fine
€40
Eduard Strasburger
1924 · Fine
€40
Eduard Strasburger
1935 · Fine
€45
Ernest Thompson Seton
1929 · Fine
€35
Frederick Soddy
1935 · Fine
€30
Romain Rolland
1918 · Fine
€50
Antoni Christiaan Winand Staring
1900 · Fine · NL
€30
Hilaire Belloc
1929 · Fine
€35
Ernst Heinrich Philipp August Haeckel
1900 · Fine
€30
Carl David Tolmé Runge
1916 · Fine
€50
Jesse Feiring Williams
1924 · Fine
€35
Abraham Kuyper
1911 · Fine · NL
€30
Inge, William Ralph
1926 · Fine
€50
Morris Raphael Cohen
1935 · Fine
€35
Alexis Thomson
1912 · Fine
€30
John Dewey
1910 · Fine
€30
Gilbert Keith Chesterton, Catholic Way Publishing Staff
1913 · Fine
€35
Theodore Shennan
1912 · Fine
€45
G. H. Hardy, J. G. Leathem
1916 · Fine
€35
James Martineau
1923 · Fine
€40
H. Newell Martin, Ernest Gale Martin
1904 · Fine
€40
George M. Gould
1900 · Fine
€35
Rudolf Otto
1929 · Fine
€35
E. B. Jamieson
1914 · Fine
€40
Walter E. Thirring
1906 · Fine
€40
George Bernard Shaw
1927 · Fine
€30
Maurice Henry Hewlett
1926 · Fine
€45
Pieter Joseph Cruse
1911 · Fine · NL
€30
Alfred North Whitehead
1930 · Fine
€40
Jean-Jacques Rousseau
1927 · Fine
€30
Mary Greer Conklin
1923 · Fine
€40
Ika A. Thomése
1935 · Fine · NL
€35
Willem Jan Maria Westerwoudt
1915 · Fine · NL
€40
Henry Sinclair Hall, Samuel R. Knight
1904 · Fine
€30
Karl Pearson
1934 · Fine
€30
Klaas Johan Pen
1935 · Fine · NL
€35
Guillaume Groen van Prinsterer
1903 · Fine · NL
€30
Rudolf Steiner
1932 · Fine
€40
Maximilien Marie
1925 · Fine
€35
Erwin Madelung
1935 · Fine
€40
Henri Poincaré
1910 · Fine
€30
George Sydenham Clarke
1910 · Fine
€30
Antonio Machado
1935 · Fine
€30
Gerard Manley Hopkins
1920 · Fine
€45
Charles David Hodgman
1916 · Fine
€45
Lewis Beesly, Thomas Baillie Johnston
1928 · Fine
€50
John Reed
1932 · Fine
€40
Annie L. Burton
1910 · Fine
€30
Jan van Leeuwen
1935 · Fine · NL
€45
H. G. Wells
1919 · Fine
€35
Rudyard Kipling
1920 · Fine
€40
Wood, Robert Williams
1919 · Fine
€40
Steven S. Zumdahl
1915 · Fine
€45