if (class_exists('MultiPostThumbnails')) {
			new MultiPostThumbnails(array(
			'label' => 'Secondary Image',
			'id' => 'second-image',
			'post_type' => 'project'
			));
				
			new MultiPostThumbnails(array(
			'label' => 'Tertiary Image',
			'id' => 'third-image',
			'post_type' => 'project'			
			));
}	
add_image_size('project-second-image-thumbnail', 100, 100);
add_image_size('project-third-image-thumbnail', 100, 100);