Hierarchy Icon in Material Style

This Hierarchy icon is made in Material Design style developed by Google. This style is based on extremely simplified shapes, thin two-pixel lines, and is optimized for 24x24 px. Unlike other vector icon packs that have merely hundreds of icons, this icon pack contains 4,700 icons, all in the same style and quality.
There is a small rounded square above three equally sized and shaped squares below it. There is a line connecting the top square directly to the one below and another line reaching from the top of the bottom left square crossing the middle line and connecting to the bottom right square.

Idea of Hierarchy Icon by John Mando

We've received the idea on August 08, 2012 and created the icons on January 23, 2013

Serial and parallel tasks, approvals