Philip Willis. Projective Alpha Colour. Comput. Graph. Forum, 25(3):557-566, 2006. [doi]
@article{Willis06a, title = {Projective Alpha Colour}, author = {Philip Willis}, year = {2006}, url = {http://www.eg.org/EG/CGF/volume25/issue3/v25i3pp557-566.pdf}, researchr = {https://researchr.org/publication/Willis06a}, cites = {0}, citedby = {0}, journal = {Comput. Graph. Forum}, volume = {25}, number = {3}, pages = {557-566}, }