Heraldischer Atlas; eine Sammlung von heraldischen Musterblättern für Künstler, Gewerbetreibende, sowie für Freunde der Wappenkunde was a book on heraldry by Austrian heraldist and heraldic artist Hugo Gerard Ströhl, published in Stuttgart in 1899. As the title says, it was intended as a model book for how coats of arms should be drawn.
This large volume is still considered a standard work in German heraldic literature. The English book The Art of Heraldry: An Encyclopædia of Armory (1904) by Arthur Charles Fox-Davies incorporates its plates and much of its text translated to English.
The book is now in the public domain and free to copy; since its creator died in 1919, copyright expired in 1989.