1. Standard Methods for the Examination of Water and Wastewater,1992
2. Northstar Produce Inc. Recalls Granny Smith Size 175 Apples Because of Possible Health Risk,2015
3. Jack Brown Produce, Inc. Recalls Gala, Fuji, Honeycrisp and Golden Delicious Apples Due to Possible Health Risk,2017
4. North Bay Produce Voluntarily Recalls Fresh Apples Because of Possible Health Risk,2019
5. Code of Federal Regulations Title 21. Sec 173.315,2020