1. A note on unrestricted solutions of the differential equation Δu = f(u);Haviland;J. London Math. Soc.,1951
2. Electrohydrodynamics I. The equilibrium of a charged gas in a container;Keller;J Rational Mechanics and Analysis,1956
3. Über ganze Lösungen der Differentialgleichung Δu = f(u);Walter;Jahresber. Deutsch. Math. Verein,1955
4. On the inequality Δu⩾f(u);Osserman;Pacific J. Math.,1957
5. Ganze Lösungen der Differentialgleichung Δu = eu;Wittich;Math. Z.,1944