code: function parse_PtgRefN(blob, length, opts) {
  	var type = (blob[blob.l] & 0x60)>>5;
  	blob.l += 1;
  	var loc = parse_RgceLocRel(blob, 0, opts);
  	return [type, loc];
  }
docs: /* [MS-XLS] 2.5.198.88 ; [MS-XLSB] 2.5.97.72 TODO