In German language.
Peter Baumann describes his techniques in making his miniature embroideries, and his choice of fabrics and using textile paints, which I find helpful.
He also shares the instructions to numerous projects, including slightly larger than 4cm squares, like the oval one in the book cover. The patterns are actual sizes (below: 4cm x 4cm).
He has a website and you can try reading it in english through google´s translate: http://baumann-gesticktelandschaften.de/
He has been embroidering and exhibiting since 1986, and has also won several embroidery competitions. He was a skilled mason and a policeman.
You can purchase his book in amazon.