images = new Array(3);

images[0] = "<img src='http://www.pvdagroenlinkszeewolde.nl/joombla/images/header/foto1.jpg'>";

images[1] = "<img src='http://www.pvdagroenlinkszeewolde.nl/joombla/images/header/foto2.jpg'>";

images[2] = "<img src='http://www.pvdagroenlinkszeewolde.nl/joombla/images/header/foto3.jpg'>";

index = Math.floor(Math.random() * images.length);

document.write(images[index]);

//done