Some suggestions, hope they're useful :
Sebastian A. Wagner, The Extent to which 'Consciousness' poses a problem for the Computational Theory of Mind. ISBN 10: 3640896572 / ISBN 13: 9783640896578
Published by GRIN Verlag, 2016.
Schneider, S., The Language of Thought: A New Philosophical Direction. ISBN 10: 0262527456 / ISBN 13: 9780262527453
Published by MIT Press Ltd, United States, 2015.
Pinker, S., Language, Cognition, and Human Nature. ISBN 10: 0190259280 / ISBN 13: 9780190259280
Published by Oxford University Press Inc, United States, 2015. (Chapter on the computational architecture of the mind.)
Horst, S.W., Symbols, Computation, and Intentionality: A Critique of the Computational Theory of Mind. ISBN 10: 1466348135 / ISBN 13: 9781466348134
Published by Createspace Independent Publishing Platform, 2011.
Jane Duran, Epistemics: Epistemic Justification Theory Naturalized and the Computational Model of Mind. ISBN 10: 0819173282 / ISBN 13: 9780819173287
Published by University Press Of America, 1989.
Pylyshyn, Zenon W., Meaning and Cognitive Structure: Issues in the Computational Theory of Mind.ISBN 10: 0893913723 / ISBN 13: 9780893913724
Published by Ablex Pub Corp,, 1986.