"Opensky Q&A". OpenSky. Petworks.co.jp. 2007. Retrieved 2010-02-23. A total of 2 airframes were built from this design, including a practice preliminary glider and a Jet engine installed self-powered aeroplane. [With no intention to mass-produce.] (この機体は、訓練用の初級滑空機とジェットエンジンを載せた自作航空機の2機を制作し、合計2機で運用の予定です。（量産化の予定はいまのところありません）)
"Opensky Q&A". OpenSky. Petworks.co.jp. 2007. Retrieved 2010-02-23. Can this airframe fly by itself immediately? As of 2007, a test model M-02J installed with a jet engine that can make it fly by itself is planned. The current airframe is being modified and tested. (■この機体は、今すぐ自力で飛べるの？□2007年には自力で飛べるようなジェットエンジンを搭載した試作機M-02Jを作る予定で,現在機体の改造やテストなど行っています。)
Hachiya, Kazuhiko. "OpenSky Q&A" (in Japanese). OpenSky Project. Retrieved 2006-10-09.
