Philips 32-Watt 12 in. T9 Circline Linear Fluorescent Tube Light Bulb, Daylight Deluxe (6500K) 262600 - The Home Depot
AMATRON ETL Listed 16" T9 24W LED Circline Bulb LED Circular Tube 5000K Daylight Frosted Lens with Non-Dimmable External Power Driver to Replace 16 inch 40W Fluorescent Circline - Led Household Light
Project 'Green' House #1: LED replacement lighting for circular fluorescent tubes // DavidJB.com // Python, Technology, Web, Linux, and more, by David Beitey
Feit Electric Color select 32-Watt EQ 12-in Cool White G24q-2 Pin Base Circline Type A LED Tube Light Bulb in the LED Tube Light Bulbs department at Lowes.com
4 Easy Ways to Change a Circular Fluorescent Light Bulb - wikiHow
File:How to wire circular fluorescent lamp.JPG - Wikimedia Commons