Gustave Caillebotte – Paris Street; Rainy Day – Google Art Project.
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Gustave Caillebotte [Public domain], via Wikimedia Commons

Hong Kong Umbrella Revolution -umbrellarevolution -umbrellamovement -occupyhk -occupyhongkong (15468365175).jpg.
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By Pasu Au Yeung [CC BY 2.0], via Wikimedia Commons

Guy with an umbrella battling rain and snow on a bridge.jpg. View here
By Thomas Leuthard from Hünenberg See, Switzerland [CC BY 2.0], via Wikimedia Commons

Hong Kong Umbrella Revolution -umbrellarevolution -umbrellamovement -occupyhk -occupyhongkong (15461699522).jpg. View here
By Pasu Au Yeung [CC BY 2.0], via Wikimedia Commons

The Lichtenberg-Kolleg historic observatory. Photograph by: Kirsch-Schroeder.