books.google.pl - The German invasion of Poland on 1 September 1939 began World War II in Europe, pitting the newly modernized army of Europe’s great industrial power against the much smaller Polish army and introducing the world to a new style of warfare – Blitzkrieg. Panzer divisions spearheaded the German assault...http://books.google.pl/books/about/Poland_1939.html?hl=pl&id=oQeAKAjlEwMC&utm_source=gb-gplus-sharePoland 1939
