1. TADOC - Technical Analysis Documentation

    tadoc.org

    Provides open source code and scripts for many TA indicators and functions.

  2. Technical Indicators & Studies - csidata.com

    www.csidata.com/?page_id=797

    The ADX is a Welles Wilder style moving average of the Directional Movement Index (DX). The values range from 0 to 100, but rarely get above 60.