this edition written and researched by Celeste Brash, Caroline Sieg, Karla Zimmerman this edition written and researched by Ryan Ver Berkmoes, Karla Zimmerman. this edition written and researched by Catherine Le Nevez and Karla Zimmerman this edition written and researched by Celeste Brash and Jean-Bernard Carillet this edition written and researched by Alison Bing, Paula Hardy. this edition written and researched by Brandon Presser, Carolyn Bain, Fran Parnell this edition written and researched by Beth Kohn, Sarah Benson this edition written and researched by Jenny Walker, Paul Clammer this edition written and researched by Karla Zimmerman this edition written and researched by Karla Zimmerman.