The various reference articles below were found on the internet to download or read online.

 

Aagaard: Inside the Chess Mind

Aagard: Excelling at Chess

Beim: How to Play Dynamic Chess

Bowman: Coaching Chess

Anonymous: Chess Openings

Crouch: Why We Lose at Chess

de Firmian: Modern Chess Openings]

Roman Dzindzichashvili on Chess Openings

Gufeld: Exploiting Small Advantages

Heisman: Looking for Trouble

Kotov: Think Like a Grandmaster

Kotov: Train Like a Grandmaster

Kotov: Play Like a Grandmaster

Lowery: Encyclopedia of Chess Openings

Lowery: Sacrificing in Chess

Miller: Quick Guide - Rules and Etiquette of Tournament Chess

Ming: The Sicilian Najdorf - 6.Bg5 (preview only)

Neishtadt: Catastrophe in the Opening

Neishtadt: Test Your Tactical Ability

Nesis: Tactics in the Sicilian

John Nun - Preview: Endgame Challenge

Silman: Endgame Study Course]

USCF Chess Rules: Ed.5 - Quick Guide

USCF Rules Summary

Van Perlo: Endgame Tactics]

Vukovic: The Art of Attack

Wall: Off-the-Wall Chess Trivia

Watson: Chess Strategy in Action