Obtained how?
Digital fonts? I highly doubt it. 
Scans? Sure. Collectors of type specimens in Germany have books with those. 

Only how to reach them ?

 

Maybe someone knows the title of the typographic catalog in which I can find these fonts.

I checked. They are in the main type specimen books (“Hauptprobe”) of those foundries from the early 20th century. 

https://www.typografie.info/3/Buecher/design-und-typografie.html/hauptprobe-der-schriftgießerei-flinsch-r91/

But be warned: as usual at that time, those pages would only show examples, not the full character set. 

I found something like that.

I wonder what catalog it comes from.

https://www.google.com/search?q=langschrift&prmd=mivn&source=lnms&tbm=isch&sa=X&ved=0ahUKEwjh0OKniIHcAhUDfFAKHep9BHEQ_AUICigC&biw=1024&bih=768#imgdii=dhGgOfRKUnlxGM:&imgrc=dhGgOfRKUnlxGM:&isa=y