Lightbulbs - Publicity photograph for Philips New Zealand Limited (1931-1940) by Ken Niven and Gordon H Burt Ltd. https://www.rawpixel.com/image/13028992/photo-image-circle-bulb-photographyFree Image from public domain licenseLight bulb png clipart illustration, transparent background. Free public domain CC0 image. https://www.rawpixel.com/image/7729748/png-white-background-peopleFree PNG from public domain licenseCartoon light bulb png illustration, transparent background. Free public domain CC0 image. https://www.rawpixel.com/image/8704266/png-people-cartoonFree PNG from public domain license