<dependency>
  <groupId>org.log4s</groupId>
  <artifactId>log4s-testing_2.11</artifactId>
  <version>1.8.1</version>
</dependency>

implementation 'org.log4s:log4s-testing_2.11:1.8.1'

implementation("org.log4s:log4s-testing_2.11:1.8.1")

libraryDependencies += "org.log4s" % "log4s-testing_2.11" % "1.8.1"

@Grapes(
  @Grab(group='org.log4s', module='log4s-testing_2.11', version='1.8.1')
)

<dependency org="org.log4s" name="log4s-testing_2.11" rev="1.8.1" />

[org.log4s/log4s-testing_2.11 "1.8.1"]

'org.log4s:log4s-testing_2.11:jar:1.8.1'