<?xml version="1.0" encoding="UTF-8"?>
<!-- 
    DTR1 BL - Boolean
    Status: draft
-->
<rule abstract="true" id="BL" xmlns="http://purl.oclc.org/dsdl/schematron" see="https://docs.art-decor.org/documentation/datatypes/DTr1_BL">
    <extends rule="ANY"/>
    <!--
    <assert test="@nullFlavor or (not(@nullFlavor) and @value)">Datatype BL: value or null</assert>
    -->
</rule>