Himitsu no Akko-chan (aka Akko-chan's Got a Secret, English title from the bilingual comics) is a manga series by Fujio Akatsuka. It's often described as the first magical girl manga series.

Here I tried to gather the books in the series. This turned out to be more complicated than expected, because there were actually two different runs of the series in Ribon Magazine, plus another one in Nakayoshi. And according to Wikipedia all the different series of collected volumes have significant differences and collect different parts of the source material.

...my source for this info is Japanese Wikipedia read with Google translate, so if it's wrong you know why!

not listed here (i.e. the ones I didn't bother adding):

Earth Shuppan-kyoku 3 volume reprint

eBookJapan 5 volume digital only version

Made in Akatsuka Fujio Akko-chan - couldn't find enough information with my meager knowledge of Japanese

work in progress

Princess Knight (リボンの騎士) is a classic manga series by Osamu Tezuka. It was first serialized in the Shoujo Club magazine in 1953. A decade later, a new version was serialized in Nakayoshi. Over the years, both versions have been released in many different formats and collections. There have also been several new series inspired by the originals, but drawn by other artists. In this list I tried organizing (almost) all of them.

(work in progress)

Not included:

Shogakukan Golden Comics Tezuka Osamu Manga Zenshuu version of vol. 1 - not adding until the conflated editions issue is sorted

The 5 volumes of the 1970s Monthly Tezuka Magazine Leo Mushi Pro version, because idk whether or not they're the same as the 5 volume Nakayoshi first release (which doesn't cover the whole story)

The January 1984 version mentioned on Wikipedia, because I couldn't find further info

The Nakayoshi ver. complete reprint special box

Maruzen Junkudo, Fukkan dot com and Little More reprints: I just couldn't be bothered to add them

The Brazilian JBC version with 8 volumes: same as above

Most international editions of the Nakayoshi version

The 1960s two-volume version of Futago no Kishi