The publications listed below provide useful information, frameworks and techniques

• Requirements Engineering, by Gerald Kotonya and Ian Sommerville (Wiley)
  (ISBN 0471972088)
• Effective Requirements Practices, by Ralph R Young (Addison Wesley)
  (ISBN 0201709120)
• Mastering the Requirements Process, by Suzanne Robertson and James Robertson (Addison Wesley)
  (ISBN 0201360462)
• Writing Better Requirements, by Ian Alexander and Richard Stevens (Addison Wesley)
  (ISBN 0321131630)
• Business Analysis Techniques: 72 Essential Tools for Success, by James Cadle, Debra Paul and Paul Turner (BCS)
  (ISBN 190612423X)