20 years ago I knit several pairs of latvian mittens and gave them all (most?) away.
I learned in the Minneapolis/ St.Paul knitting club run at that time by Lizbeth Upitis.
Lizbeth studied textile arts at Univ. and created the copiously illustrated book “Latvian Mittens”.
The book gives detailed instructions for 5 different patterns, then has plates & plates of colored photographs of more mittens. Some are 2-colored, others have 3-5 colors. Some are lined.
At the end of the book patterns for all of the illustrated mittens (and more) are shown on graph-paper.