http://takacustomlens.blogspot.com/2021/06/the-petzval-lens-spiral-world-of-8mm.html

http://fotoborse.blog.jp/archives/1927690.html

https://k-tai.watch.impress.co.jp/docs/column/minna/1441376.html

https://www.itmedia.co.jp/news/spv/2209/20/news077_0.html

https://blog.itokoichi.com/entry/2022/09/21/180000

https://netafull.net/neta-eat/0120121.html

https://netafull.net/ios-16/0119886.html

https://netafull.net/ios-16/0120130.html

https://www.dream-seed.com/weblog/60-galaxy-169699/

http://straysheep67.seesaa.net/article/385331574.html

http://annalens.seesaa.net/article/412431218.html

Mikro-Summar https://spiral-m42.blogspot.com/2014/12/ernst-leitz-summarmikro-summar-8cm-f45.html

http://www.netlaputa.ne.jp/~shima/accesorry.htm

https://news.mapcamera.com/maptimes/%E3%80%90leica%E3%80%91%E4%BB%8A%E6%97%A5%E3%81%AF%E3%81%A9%E3%81%AE%E3%82%BA%E3%83%9E%E3%83%BC%E3%83%AB%EF%BC%9F/

https://www.itmedia.co.jp/news/articles/2209/21/news088.html

https://iphone-mania.jp/news-489093/

xPeria lEaker: もう安すぎ。米SamsungがGalaxy S22 Ultraを最大79%オフでセール. https://gazyekichi96.com/2022/09/19/its-too-cheap-samsung-sells-galaxy-s22-ultra-for-up-to-79-off/