comment trouver de l'élément de l'étiquette

J'ai cette div avec l'étiquette "Nom", ce qui je veux dans mon Sélénium e2e test:

<div class="control-group ng-class: { 'error': isInErrorState() } ng-scope" dto-control-group="" label="First Name">
    <label class="control-label" for="FirstName">
        <span class="ng-binding">First Name</span>
        <span class="required-asterisk" ng-show="isRequired">*</span>
    </label>
    <div class="controls">
                <input type="text" id="FirstName" dto-input-validate="" name="FirstName" ng-model="qform.submission.persons[0].firstName" class="ng-scope ng-pristine ng-invalid ng-invalid-dtorule">

        <div class="inline-messages">
            <!-- ngIf: helpMsg -->
            <span class="error-inline ng-binding">This is a required field</span>
        </div>
    </div>
</div>

voici mon code Java:

//XXX this returns NULL
@FindBy(xpath = "//div[@label=\"First Name\"]")
private InputElement firstName;

quel est le problème ici?