1. Crossley, I., Goodridge, I.H., Cardwell, M.J., and Butlin, R.S.: ‘Growth and characterization of high-quality epitaxial gallium arsenide for microwave FETs’, Gallium arsenide and related compounds-1976, 1977), p. 289–296 IoP Conf. Series 33b
2. Butlin, R.S., Parker, D., Crossley, I., and Turner, J.: ‘Correlation between device characteristics and material quality in low noise GaAs FETs’, p. 237–245 ibid.