1. Note on the behavior of solutions of parabolic equations with unbounded coefficients;Chen;Nagoya Math. Journ.,1969
2. On the asymptotic behavior of the solutions of the equation;Szybiak;Bull. Acad. Polo. Sci.,1959
3. Evaluations des solutions de l’equation linéaire de type paraboliques à coefficients non-borné;Krzyżański;Ann. Polo. Math.
4. Fife, The unbounded growth of solutions of linear parabolic differential equations;Besala-P;Ann. Scoula Norm. Sup. Pisa III,1966
5. A strong maximum principle for parabolic equations