Condition a accepter d'un formulaire

<input type="checkbox" name="cgu" id="cgu" /> <label for="cgu">J'accepte les conditons générales d'utilisation de Tonsite.com</label>

<input type="submit" value="Envoyer" id="submitButton" style="display:none;" />

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	var submitButton = document.getElementById('submitButton');
	
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