written & researched by Cristian Bonetto... [ea al.] written & researched by Cristian Bonetto... [ea al. written and researched by Cristian Bonetto... [et al.] written and researched by Cristian Bonetto... [et al. written and researched by Cristian Bonetto and Helena Smith written and researched by Cristian Bonetto, Paula Hardy this edition written and researched by Cristian Bonetto... [et al.] written and researched by Cristian Bonetto and Helena Smith. written and researched by Damian Harper... [et al.] written and researched by Phillip Tang... [et al.]