Cita APA (7th ed.)

Castillo, M. T. (1999). On the existence of the essential spectrum for a class of differential expressions. Matimya's Matematika.

Cita Chicago (17th ed.)

Castillo, Maritina T. "On the Existence of the Essential Spectrum for a Class of Differential Expressions." Matimya's Matematika 1999.

Cita MLA (9th ed.)

Castillo, Maritina T. "On the Existence of the Essential Spectrum for a Class of Differential Expressions." Matimya's Matematika, 1999.