Equation : labour light, clothes white = Sunlight / Lever Brothers Limited. https://www.rawpixel.com/image/13952072/equation-labour-light-clothes-white-sunlight-lever-brothers-limitedFree Image from public domain licenseWorld War I: "transport of our wounded in Russia, 1918". Oil painting by Godfrey Jervis Gordon ("Jan Gordon"). https://www.rawpixel.com/image/13970618/image-person-art-clothingFree Image from public domain licenseWorld War I: transport of the wounded by sledge in Russia, 1918. Oil painting by Godfrey Jervis Gordon ("Jan Gordon"). https://www.rawpixel.com/image/13955777/image-person-art-clothingFree Image from public domain licenseDesign for a Plate (1880-1910) painting in high resolution by Noritake Factory. Original from The Smithsonian Institution.… https://www.rawpixel.com/image/2848898/free-illustration-image-pattern-noritake-japanFree Image from public domain licenseWinter Scene (Horse-Sleigh on the Ice) (1790 - 1814) by Andries Vermeulen https://www.rawpixel.com/image/13733187/winter-scene-horse-sleigh-the-ice-1790-1814-andries-vermeulenFree Image from public domain licenseWinter in the Scheveningen Woods (1870 - 1888) by Anton Mauve https://www.rawpixel.com/image/13742535/winter-the-scheveningen-woods-1870-1888-anton-mauveFree Image from public domain licenseHenriette d'Angeville and her party ascending Mont Blanc, 1838. Colour lithograph by F. Baumann. https://www.rawpixel.com/image/13964614/image-dog-cartoon-personFree Image from public domain licenseNative Americans shake hands with a Western visitor, who is shown standing beside a sledge drawn by dogs; wigwams are seen… https://www.rawpixel.com/image/13967746/image-background-dog-horseFree Image from public domain licenseA man travelling on a sledge drawn by five dogs in Kamchatka. Engraving by S. Middiman, 1784, after J. Webber. https://www.rawpixel.com/image/14002282/image-dog-horse-plantFree Image from public domain licenseSneeuwlandschap met zwaaiende figuren (c. 1890 - c. 1970) by F van Leeuwen https://www.rawpixel.com/image/13791484/sneeuwlandschap-met-zwaaiende-figuren-c-1890-1970-van-leeuwenFree Image from public domain licenseWintergezicht op de Buiten-Amstel te Amsterdam (1742 - 1801) by Georg Balthasar Probst, Georg Gottfried Winckler, P van… https://www.rawpixel.com/image/13764121/image-dog-paper-cartoonFree Image from public domain licensePotdeksel met een ijsgezicht (c. 1400 - c. 1950) by anonymous https://www.rawpixel.com/image/13748413/potdeksel-met-een-ijsgezicht-c-1400-1950-anonymousFree Image from public domain licenseSneeuwruimers op de militaire weg in Georgië (c. 1890 - c. 1900) by Dimitri Ivanovitch Ermakov https://www.rawpixel.com/image/13759821/photo-image-horse-person-clothingFree Image from public domain licenseFriese vrouwen op het ijs (1829) by Ludwig Gottlieb Portman, C F Bounach, Jan Willem Pieneman, Jacques Kuyper, Evert… https://www.rawpixel.com/image/13747799/image-paper-cartoon-faceFree Image from public domain license