STRONGMatthys Levy is a civil engineer and the inventor of the Tenstar Dome, which is used to cover athletic venues around the world. He is the coauthor of Engineering the City and Why the Wind Blows. He lives in Burlington, Vermont. STRONGMario Salvadori was a professor of architecture and the founder of the Salvadori Center, a nonprofit educational center to teach inner-city youth about math and science through hands-on study of structure and architecture. He is the author of The Art of Construction and Why Buildings Stand Up. They are the coauthors of Why Buildings Fall Down.