Professor Gumbs has published in several referred journals including --

Physical Review A, B and Physical Review Letters
http://www.aps.org

Journal of Physics
http://www.iop.org

Applied Physics Letters and The Journal of Applied Physics
http://ojps.aip.org/aplo

Superlattices and Microstructures
http://www.elsevier.com/locate/issn/0749-6036

Europhysics Letters
http://www.edpsciences.org/journal/index.cfm?edpsname=epl

Solid State Communications
http://www.elsevier.com/locate/issn/00381098

Physics Letters A
http://www.elsevier.com/locate/issn/03759601

Physica D and E
http://www.elsevier.com/locate/issn/01672789

Journal of Mathematical Physics
http://ojps.aip.org/jmp

Annals of Physics
http://www.elsevier.com/locate/issn/0003-4916