function vtour( _step ) {
 
 step_name_en = [ 
 		   "The discovery of X-Rays",
 		   "X-Rays: from Radiology to Materials Research",
		   "How does synchrotron light work ?",
		   "The Many Virtues of the Synchrotron Sources",
		   "Wigglers and Undulators",
		   "Using Synchrotron Light",
		   "Photoelectron Spectroscopy",
		   "Crystallography and X-Ray Scattering",
		   "Mammography deep-etch lithography and proximity photo lithography",
		   "A Typical Day at ELETTRA"
		   ];

 step_name_it =[
 		   "Inizia il giro, la scoperta dei raggi-X",
		   "Raggi-X: dalla radiologia alla ricerca sui materiali",
		   "Come funziona ?",
		   "I tanti vantaggi delle sorgenti di sincrotrone",
		   "Wigglers e ondulatori",
		   "Usare la luce di sincrotrone",
		   "Spettroscopia fotoelettronica",
		   "Cristallografia e scattering a raggi-X",
		   "Mammografia",
		   "Una tipica giornata ad ELETTRA"
		   ];

 if( language == "en" ) {
 	  step_name =step_name_en;
 	  prefixo ="";
	  next = "continue";   
 } else {
 	  step_name =step_name_it;
	  prefixo ="it-";
	  next = "continua";
 }

 with( document ) {
 	   if( _step < 10 ) {
	   	   s =(_step +1);
 		   if( _step < 9 ) s ="0" +s;
		   
	   	   writeln( '<a href="' +prefixo +'vtour_p' +s +'.html">' +next +'...</a>' );
	   }

 	   writeln( '<br>\n<hr width="30%">\n<ul>' );

 	   for( i = 0; i < step_name.length; i++ )
 	   		if( _step-1 == i ) writeln( '<li class="active"><u><span class="active">' +step_name[i] +'</span></u></li>' );
	  		else {
				 s =(i +1);
				 if( i < 9 ) s ="0" +s;
				 
				 writeln( '<li><a href="' +prefixo +'vtour_p' +s +'.html">' +step_name[i] +'</a></li>' );
			}

 		writeln( '</ul>' );
 }
}