Fourier and Poisson both students of Lagrange
Specker and Eckmann both students of Hopf
Johann Bernoulli --------------------------------- Hausen
Euler ------------------------------------- Kaestner
Lagrange -------------------------------- Pfaff
Fourier + Poisson -------------------- Gauss
Dirichlet 1827 --------------- Gerling
Lipschitz 1853 + Pluecker 1823
F. Klein 1868
C. Lindemann 1873
D. Hilbert 1885
E. Schmidt 1905
H. Hopf 1925
E. Specker 1947 + B. Eckmann 1944
H. Laeuchli 1963
J.A. Makowsky 1974