The <a href="https://en.wikipedia.org/wiki/Convention_on_Psychotropic_Substances" id="mwzg" rel="mw:WikiLink" title="Convention on Psychotropic Substances">Convention on Psychotropic Substances</a> is signed at <a href="https://en.wikipedia.org/wiki/Vienna" id="mwzw" rel="mw:WikiLink" title="Vienna">Vienna</a>.