function position(y,m,ym,now_m){
if(ym == ""){
	location.replace("../kagaku/index.php");
	}
chck_m = m;
document.write('        <table width="170" border="0" cellspacing="0" cellpadding="0">');
document.write('          <tr>');
document.write('            <td><img src="images2/mokuroku_top.gif" alt="月刊化学" width="170" height="20"></td>');
document.write('          </tr>');
document.write('        </table>');
m = m - 0;
if(m == now_m){
document.write('        <table width="170" border="0" cellpadding="5" cellspacing="0" bgcolor="#AFC1E4">');
}
else{
document.write('        <table width="170" border="0" cellpadding="5" cellspacing="0" bgcolor="#E9E9E9">');
}
document.write('          <tr class="font13">');
document.write('            <td width="50">');
document.write('              <div align="center"><img src="images2/new.gif" width="36" height="13"></div></td>');
document.write('            <td width="120"><strong><a href="' + ym + '.html?' + ym + '&' + m + '">' + y + '.' + m + '月号</a></strong></td>');
document.write('          </tr>');
document.write('        </table>');

bym = ym;
by = y;

for(i = 1;i <= 11;i++){
	document.write('        <table width="170" border="0" cellspacing="0" cellpadding="0">');
	document.write('          <tr>');
	document.write('            <td height="1" bgcolor="#333333"><img src="images2/space.gif" width="1" height="1"></td>');
	document.write('          </tr>');
	document.write('        </table>');

	check_m = m - i;
	if(check_m <= 0){
		if(check_m == 0){
		bym=bym-88;
		by=by-1;
		}
	check_m = check_m + 12;
	}
	if(now_m == check_m){
		document.write('        <table width="170" border="0" cellpadding="5" cellspacing="0" bgcolor="#AFC1E4">');
	}
	else{
		document.write('        <table width="170" border="0" cellpadding="5" cellspacing="0" bgcolor="#E9E9E9">');
	}
	document.write('          <tr class="font13">');
	document.write('            <td width="50">');
	document.write('              <div align="center"><img src="images2/space.gif" width="36" height="13"></div></td>');
	check_ym = bym - i;
	document.write('            <td width="120"><strong><a href="' + check_ym + '.html?' + ym + '&' + check_m + '">' + by + '.' + check_m + '月号</a></strong></td>');
	document.write('          </tr>');
	document.write('        </table>');
	
}
document.write('        <table width="170" border="0" cellspacing="0" cellpadding="0">');
document.write('          <tr>');
document.write('            <td><img src="images2/mokuroku_under.gif" width="170" height="10"></td>');
document.write('          </tr>');
document.write('        </table>');
document.write('        <br>');


document.write('        <form name="form1">');
document.write('          <select name="menu1" onChange="MM_jumpMenu(\'parent\',this,0)">');
document.write('            <option selected>バックナンバー</option>');

for(pully = y-1;pully>=1996;pully--){
	document.write('            <option value="chem_' + pully + '.html?' + ym + '">' + pully + '年</option>');
}

document.write('          </select>');
document.write('        </form>');
}