Robuta

https://www.kunaicho.go.jp/e-okotoba/02/press/gaikoku-h20az-spain.html

https://en.wikisource.org/wiki/Translation:The_Matter_of_the_Succession_to_the_Imperial_Throne_by_His_Highness_the_Crown_Prince_Akihito

https://www.kunaicho.go.jp/e-okotoba/02/press/gaikoku-h25az-spain.html

https://www.prnewswire.com/news-releases/his-imperial-highness-prince-ermias-sahle-selassie-haile-selassie-announces-the-formation-of-the-royal-ethiopian-trust-302263409.html