Bullock, J., & De Paula, F. C. (1966). Research and development: The key to future profitability. General educational Trust of the Institute of Chartered Accountants in England and Wales..

Bullock, J., and Frederic Clive De Paula. Research and Development: The Key to Future Profitability. Lond.: General educational Trust of the Institute of Chartered Accountants in England and Wales., 1966.

Bullock, J., and Frederic Clive De Paula. Research and Development: The Key to Future Profitability. General educational Trust of the Institute of Chartered Accountants in England and Wales., 1966.