src/it/projects/multimodule/multimodule-sourceNotBinaries/pom.xml

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/maven-v4_0_0.xsd">
  <modelVersion>4.0.0</modelVersion>
  <parent>
    <groupId>org.apache.maven.plugin.assembly.test</groupId>
    <artifactId>it-project-parent</artifactId>
    <version>1</version>
  </parent>
  
  <groupId>org.test</groupId>
  <artifactId>parent</artifactId>
  <packaging>pom</packaging>
  <version>1.0</version>
  
  <name>Parent</name>

  <modules>
    <module>child1</module>
    <module>child2</module>
    <module>child3</module>
  </modules>

  <build>
    <plugins>
      <plugin>
        <groupId>org.apache.maven.plugins</groupId>
        <artifactId>maven-assembly-plugin</artifactId>
        <inherited>false</inherited>
        <configuration>
          <descriptors>
            <descriptor>src/assemble/src.xml</descriptor>
          </descriptors>
        </configuration>
        <executions>
          <execution>
            <id>package</id>
            <phase>package</phase>
            <goals>
              <goal>directory-inline</goal>
            </goals>
          </execution>
        </executions>
      </plugin>
    </plugins>
  </build>
</project>