Thank you for the link. Unfortunately there isn't quite enough information there to give you a definite answer.
The speakers are 6 ohms so I would say you need an amp of between 20-50 watts into 6 ohms.
Power ratings on amplifiers are often exaggerated but anything in the range of 10-75 watts will work. If you have too much power you can blow the woofer when you play it louder than it can handle. If you have too little you can damage the tweeter when the amplifier distorts by its' being unable to play as loud as you have set the volume to do.