1. G. Birkhoff, Journal of the Society for Industrial and Applied Mathematics vol. 2 (1954) pp. 57-67.
2. Annals of Mathematics Studies, No. 19;Bochner, S.,1949
3. Fourier transforms of rapidly increasing functions and questions of uniqueness of the solution of Cauchy’s problem;Gel′fand, I. M.;Uspehi Matem. Nauk (N.S.),1953
4. \bysame, J. Math. Pure Appl. vol. 4 (1956) pp. 383-413.
5. American Mathematical Society Colloquium Publications, Vol. 31;Hille, Einar,1948