apidoc extension fails to install

I try to install the apidoc extention of yii2 with:

php composer.phar require --prefer-dist yiisoft/yii2-apidoc

I get following error, that composer had a problem to install cebe/markdown

Who could help?

Thx, Cihan

[color="#006400"]/* Moved from "General Discussions" to "Extensions" */[/color]

The error message would be helpful

I attachted it.

Thx, Cihan

is theire someone who had the same issue and could solve it?