function init() {
	document.onkeydown = register;
}

function register(e) {
	var code;

	if (!e) e = window.event;

	if (e.keyCode) 
		code = e.keyCode;
	else if (e.which) 
		code = e.which;

	if ((code == 37) && (e.ctrlKey == true)) {
		var destination = document.getElementById('prev_page');
		if (destination) 
			location.href = destination.href;
	}

	if ((code == 39) && (e.ctrlKey == true)) {
		var destination = document.getElementById('next_page');
		if (destination) 
			location.href = destination.href;
	}

}