made default for external source documents --> EXPLANATION
made default for external source documents --> EXPLANATION

raccoongang/socraticqs2,cjlee112/socraticqs2,raccoongang/socraticqs2,derdmitry/socraticqs2,raccoongang/socraticqs2,derdmitry/socraticqs2,cjlee112/socraticqs2,cjlee112/socraticqs2,derdmitry/socraticqs2,cjlee112/socraticqs2,raccoongang/socraticqs2