https://creativecommons.org/publicdomain/zero/1.0/https://www.rawpixel.com/image/13969924Edit ImageSaveSaveEditCropCustom TextInternational Airship Exhibition, Frankfurt, 1909: a Zeppelin airship, an aeroplane and two balloons airborne over the exhibition site. Process print.Original public domain image from Wellcome CollectionMorePublic DomainFree CC0 image for Personal and Business useInfoView CC0 LicenseJPEGSmall JPEG 1200 x 768 px | 300 dpiLarge JPEG 3426 x 2194 px | 300 dpiFree DownloadInternational Airship Exhibition, Frankfurt, 1909: a Zeppelin airship, an aeroplane and two balloons airborne over the exhibition site. Process print.More