code: public static String referenceIdentifierToString(byte[] ref, short stratum, byte version) {
  	// From the RFC 2030:
  	// In the case of NTP Version 3 or Version 4 stratum-0 (unspecified)
  	// or stratum-1 (primary) servers, this is a four-character ASCII
  	// string, left justified and zero padded to 32 bits.
  	if (stratum == 0 || stratum == 1) {
  	    return new String(ref);
  	}
  
  	// In NTP Version 3 secondary servers, this is the 32-bit IPv4
  	// address of the reference source.
  	else if (version == 3) {
  	    return unsignedByteToShort(ref[0]) + "." + unsignedByteToShort(ref[1]) + "." + unsignedByteToShort(ref[2]) + "." + unsignedByteToShort(ref[3]);
  	}
  
  	// In NTP Version 4 secondary servers, this is the low order 32 bits
  	// of the latest transmit timestamp of the reference source.
  	else if (version == 4) {
  	    return "" + ((unsignedByteToShort(ref[0]) / 256.0) + (unsignedByteToShort(ref[1]) / 65536.0) + (unsignedByteToShort(ref[2]) / 16777216.0)
  		    + (unsignedByteToShort(ref[3]) / 4294967296.0));
  	}
  
  	return "";
      }
docs: Returns a string representation of a reference identifier according to the rules set out in RFC
  2030.
  
  @param ref
  @param stratum
  @param version
  @return