written and researched by Alexis Averbuck, Oliver Berry and Nicola Williams. this edition written and researched by Alexis Averbuck, Oliver Berry and Nicola Williams written and researched by Duncan Garwood and Nicola Williams. written and researched by Catherine Le Nevez, Christopher Pitts, Nicola Williams. written and researched by Alexis Averbuck... [et al. written and researched by Alexis Averbuck... [et al.] written and researched by Regis St Louis and Sally Davies. written and researched by Paul Gray and Lucy Ridout. this edition written and researched by Catherine Le Nevez, Christopher Pitts, Nicola Williams. written and researched by Oliver Berry, Belinda Dixon