@font-face {
  font-family: 'Avenir Book';
  src: url('avenirltstdbook.eot');
  src: url('avenirltstdbook.eot?#iefix') format('embedded-opentype'),
       url('avenirltstdbook.woff') format('woff'),
       url('avenirltstdbook.ttf')  format('truetype'),
       url('avenirltstdbook.svg#avenirltstdbook') format('svg');
}