function previousNext() {
	var page=["P1_0.htm","P2_1.htm","P2_2.htm","P2_3.htm","P2_4.htm","P2_5.htm","P2_6.htm","P3_1.htm",
				"P3_2.htm","P4_1.htm","P4_2.htm","P4_3.htm","P4_4.htm","P5_0.htm","P6_1.htm","P6_2.htm",
				"P6_3.htm","P6_4.htm","P6_5.htm","P7_0.htm","P8_1.htm","P8_2.htm","P8_3.htm","P8_4.htm","P8_5.htm",
				"P8_6.htm","P9_1.htm","P9_2.htm","P10_0.htm","P11_0.htm"];
	var indexPage=0;
	var styleLink="previewNext";
	var toWrite;	
	var currentPage=top.location.href;

	while(currentPage.indexOf("/") != -1)  //recherche la page active
	{
		currentPage=currentPage.slice(currentPage.indexOf("/")+1);
	}
	
	while(page[indexPage] != currentPage)  //recherche la position de cette page dans la table "page"
	{
		indexPage++;
	}
		
	if(indexPage != 0)   //construit le code HTML pour les links ' [ Previous | Next ] '
	{
		toWrite="[ <a href=\"" + page[indexPage - 1] + "\" class=\"" + styleLink + "\">Previous</a> ";
		if((indexPage + 1) != page.length)
		{
			toWrite=toWrite + "| <a href=\"" + page[indexPage + 1] + "\" class=\"" + styleLink + "\">Next</a> ] ";
		}
		else
		{
			toWrite=toWrite + "] ";
		}
	}
	else
	{
		toWrite="[ <a href=\"" + page[indexPage + 1] + "\" class=\"" + styleLink + "\">Next</a> ] ";
	}
	
	document.write(toWrite);
}