. Administration Books

Some of the books which I feel are helpful if you are starting with Basis Administration :

• SAP R/3 System Administration
  German title: SAP R/3 Systemadministration

• SAP Performance Optimization Guide
  German title: SAP Performanceoptimierung

• SAP Change and Transport Management
  German title: SAP Änderungs- und Transportmanagement
  

• SAP Security and Authorizations
  German title: Sicherheit und Berechtigungen in SAP-Systemen