this edition written and researched by Ryan Ver Berkmoes. this edition written and researched by John Lee this edition written and researched by Damian Harper, Dai Min. this edition written and researched by Austin Bush. this edition written and researched by Iain Stewart and three others. this edition written and researched by Andrea Schulte-Peevers. this edition written and researched by Virginia Maxwell. this edition written and researched by Korina Miller and seven others. this edition written and researched by Cristian Bonetto this edition written and researched by Belinda Dixon [and others].