Which battery to order for replacement; Which is the correct one?

1. Dell website: Recommended Battery:
   3-cell Lithium Ion Battery from Dell™ . With a capacity of up to 42 Wh
   Manufacturer part 9W9MX | Dell part CPL-9W9MX | Order Code cpl-9w9mx | Dell
2. Installed batteries:
   NAME : DELL DM3WC64
   MANUFACTURER : SMP
   SERIAL NUMBER : 1899
   CHEMISTRY: LiP
   DESIGN CAPACITY: 60,002 mWh
   FULL CHARGE CAPACITY: 5,373 mWh