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Resources share the relationship contributor to Sill, John
- Another field guide to little-known & seldom-seen birds of North America, by Ben L. Sill, Cathryn P. Sill, John C. Sill ; illustrations by John C. Sill
- A field guide to little-known & seldom-seen birds of North America, by Ben L. Sill, Cathryn P. Sill, John C. Sill ; illustrations by John C. Sill
- About crustaceans, a guide for children, written by Cathryn Sill ; illustrated by John Sill
- About raptors, a guide for children, Cathryn Sill ; illustrated by John Sill