Second Half of the 19th and Early 20th Centuries The art of the 20th and 21st centuries Paperweights of the 19th & 20th Centuries Popular Glass of the 19th & 20th Centuries russian choral music of the 17th and 18th centuries Rings of the 20th and 21st centuries : Translation and modernization in East Asia in the 19th and early 20th centuries French studies of the Eighteenth and Nineteenth centuries Chinese and Arab trade in the twelfth and thirteenth centuries Warfare in the 16th to 19th centuries