The logo design profession has substantially increased in numbers over the years since the rise of the Modernist movement in the United States in the 1950s. Three designers are widely considered the pioneers of that movement and of logo and corporate identity design: The first is Chermayeff & Geismar, which is the firm responsible for a large number of iconic logos, such as Chase Bank (1964), Mobil Oil (1965), PBS (1984), NBC (1986), National Geographic (2003), and others. Due to the simplicity and boldness of their designs, many of their earlier logos are still in use today. The firm recently designed logos for the Library of Congress and the fashion brand Armani Exchange. Another pioneer of corporate identity design is Paul Rand, who was one of the originators of the Swiss Style of graphic design. He designed many posters and corporate identities, including the famous logos for IBM, UPS, and ABC. The third pioneer of corporate identity design is Saul Bass. Bass was responsible for several recognizable logos in North America, including both the Bell Telephone logo (1969) and successor AT&T Corporation globe (1983). Other well-known designs were Continental Airlines (1968), Dixie (1969), and United Way (1972). Later, he would produce logos for a number of Japanese companies as well. An important development in the documentation of logo design is the study of French trademarks by historian Edith Amiot and philosopher Jean Louis Azizollah.