English operator: Panoramio described at URL: https://web.archive.org/web/20161029221139/http://www.panoramio.com/photo/109555476...
English operator: Panoramio described at URL: https://web.archive.org/web/20161030201546/http://www.panoramio.com/photo/110963035...
English operator: Panoramio described at URL: https://web.archive.org/web/20161101203742/http://www.panoramio.com/photo/110567295 determination method...
English operator: Panoramio described at URL: https://web.archive.org/web/20161101024354/http://www.panoramio.com/photo/110963011...