If you play three-band billiards, you need billiards systems to take your game to the level of somebody. This book series can help you with that. In the first level, the "44" system is described.
Since there are players at various levels, I tried to prepare the levels at certain levels. If you have not used any system before and you are just starting to start systems, I recommend you to start here. Because in this book, there are basic systems that should be known first, how to make calculations, application methods, stroke techniques and more. I have also included various tips that I think will be useful for you in the game.
It is for players who know the system calculations in later levels (Level 2 and Level 3) and want to advance them. You can find all the levels of the series in a single book "Level 1-2-3".