Yes. Always start with the fat one (Cindy, I think). She's the one who casts wall and revive the others, and she has the most HP of the three. Just smack her without using magic until she falls.

Next, I always take the small one (Mindy, I think), because if I recall well, she uses magic attacks and has more HP than the tall one. Pound her with everything you have, then once you finish her off, you only have the tall one left. Tall one is a wuss.

Just keep an eye on your HP and MP, use Cure spells and potions when necessary, and you should be alright.

Also recommended, but not mandatory, is to use a tent or cabin and save before moving on, because you'll have to face Valvalis not two minutes later.