Is there a research scheme? (XCOM: Enemy Unknown)

Nobody bothers, there is no special scheme there - a new one caught - a new research, a new ship was shot down - another research - a key moment of the game - another research.

RIPxxx Do

n't tell me. For a strategy, you need to have a plan. And the Tech Tree is sorely lacking. In order to clearly understand how something is split up in the shortest possible time.

Complete research outline for XCOM: Enemy Unknown and XCOM: Enemy Within.
Translated by me.
Original taken from http://www.xdude.com/xcom/

The most convenient thing that I found:
https://tacticsquad.ru/rukovodstva-k-xcom/tehnologii-xcom-enemy-unknown-i-xcom-enemy-within

Other schemes confuse me more than make the tree understand.