Ohio State University Extension, Ohioline Food Preservation Fact Sheets - http://ohioline.osu.edu/topic/food

National Center for Home Food Preservation - http://nchfp.uga.edu/

USDA Complete Guide to Home Canning and Purdue Extension Food Preservation Factsheets - https://www.extension.purdue.edu/usdacanning/

Presto Industries - http://www.gopresto.com/products/manuals.php

Jarden Industries (Ball, Kerr, Fruit Fresh, etc) - http://www.freshpreserving.com/

Surejell - http://www.kraftrecipes.com/sure-jell.aspx