function toggleYear(year) {
	var liYear = objId('li'+year);
	var ulMonth = objId('ul'+year);
	
	if (liYear.className == "selected") {
		liYear.className = "";
		if (ulMonth != null) {		
			ulMonth.style.display = "none";
		}
	}
	else {
		liYear.className = "selected";
		if (ulMonth != null) {		
			ulMonth.style.display = "";
		}
	}
}

function toggleMonth(year,month) {
	var liMonth = objId('li'+year+month);
	var ulArticles = objId('ul'+year+month);	
	
	if (liMonth.className == "selected") {
		liMonth.className = "";
		if (ulArticles != null) {
			ulArticles.style.display = "none";
		}
	}
	else {
		liMonth.className = "selected";
		if (ulArticles != null) {
			ulArticles.style.display = "";
		}
	}
}