function changeBookmarkOnTop(view){
 document.getElementById("view1").style.display = "none";
 document.getElementById("view2").style.display = "none";
 document.getElementById("bookLink1").className = "";
 document.getElementById("bookLink2").className = "";
 document.getElementById("view"+view).style.display = "";
 document.getElementById("bookLink"+view).className = "active";
}