Ruy Lopez (Berlin Defence)(C65-67) - Opening Theory

Ruy Lopez (Spanish) Berlin Defense

1.e4 e5 2.Nf3 Nc6 3.Bb5 Nf6

Wikipedia page 
 The Berlin Defence, 3...Nf6, has long had a reputation for solidity and drawishness and is commonly referred to as "the Berlin Wall"

BOOKS (Free)

The Modenized Ruy Lopez  Vol 1 A Complete Repertoire for White - 18 Page (Chap. 2 Birds)  PDF
500 Ruy Lopez Miniatures By Bill Wall  - 122 Page PDF
Easy Guide to Ruy Lopez by John Emms  - 74 Page PDF

Free Chessable Course

Short & Sweet: Berlin Defense MoveTrainer™ Opening course by GM Sam Shankland - 20 Trainable Variations with 32 Min of Video

Ruy Lopez (Berlin Defense) Articles

Berlin Defense: Complete Guide - Solid article by FM Zaur Tekeyev
The Mortimer Trap - It's only natural that it should be rediscovered, given the recent popularity of the Berlin Defense to the Spanish / Ruy Lopez 

Berlin Defense LiChess Studies

Black Repertoire - Ruy Lopez: Berlin Defense - 29 Chapters
Berlin Defense variations: Ruy Lopez  - 9 Chapters
Berlin Defense: Chess Opening Study - 17 Chapters

Games Databases

Chessgames.com 
Berlin Defence Games - 1100+ Games at you can go through online.
365Chess.com
C65: Ruy Lopez, Berlin defence - Link Page to all the Sub- Varients and 18,000 games at 
  Annotated Games
Svidler vs Topalov 2006 - A nicely Annotated game from the ChessVault.com
Nisipeanu vs Topalov 2006 - Annotated by Mihail Marin 
 Hou Yifan vs Nigel Short - Washington post article on the 13 yr old girl beating Short. 

 Ruy Lopez Berlin Defense Chess Video Lessons

Ruy Lopez - Berlin Defense ⎸Chess Openings - 20 Min
The Berlin Defence in the Ruy Lopez - GM Yasser Seirawan  - 48 Min
GM Sam Shankland: The Berlin Defense | U.S. Chess School - 52 Min  Chess Dojo
The Ruy Lopez | Berlin Defense | Chess Openings | IM Andrey Ostrovskiy - 15 Min
Beat the Ruy Lopez with the Berlin Variation - GM Leonid Kritz - 15 Min

Play Against the Berlin

How To Play Against The Berlin Defense ⚔ Chess Openings For White - 16 min - GM Gufstason

Berlin Defense Chess Traps

Indian Prodigy REFUTES the Berlin Defense??! | Ruy Lopez opening TRAP - 11 Min
Dirty Chess Tricks 63 (Trick the Berlin/Spanish/Ruy Lopez) - 15 Min
Spanish Game: Berlin Defense chess trap 18 - 8 Min
Chess Traps #5: Ruy Lopez Berlin Defence Trap (Fishing Pole) - 8 Min
Mortimer Trap | Berlin Defense in the Ruy Lopez | Opening Tricks and Traps to Win Fast - 7 Min
Dirty Chess Tricks 63 (Trick the Berlin/Spanish/Ruy Lopez) -15 Min

Berlin Defense Game Videos /w Analysis

Berlin Defence : GM Judit Polgar vs GM Sergey Karjakin - Spanish Game - 20 Min
Judit Polgar defeats Garry Kasparov in the Spanish Game - Berlin defence - 17 Min
I turned the Berlin into the MOST AGGRESSIVE GAMBIT EVER and CRUSHED Stockfish with it - 13 Min
GM Fabiano Caruana Vs GM Pavel Eljanov - Russian Team Championship 2011 - Berlin Defense Ruy Lopez - 12 Min
Berlin Defence : GM Judit Polgar vs GM Sergey Karjakin - Spanish Game (Berlin Defense) - 20 Min