Ion-icon not showing in my app

Hi AaronSterling and thank you for reply. Here is my HTML for this view, it is very simple:

<ion-view view-title="{{properties.item.lastName}} - {{properties.item.firstName}}">
    <ion-nav-bar class="bar-positive">
        <ion-nav-back-button class="button-clear">
            <i class="ion-chevron-left"></i> Back
        </ion-nav-back-button>
    </ion-nav-bar>
    <ion-content>
        <ion-list>
            <ion-item ng-repeat="info in infos">
                {{info.firstName}} - {{info.lastName}}
                <ion-icon name="person"></ion-icon>
            </ion-item>
        </ion-list>
    </ion-content>
</ion-view>

I tried for another icons for test for example "home", "call" but unfortunately those aren't work.
In other piece of code use of icon does not works too:

<div ng-if="properties.infoType == 'jobs'">
	<button class="button button-block">{{properties.workName}}</button>
	<div class="item item-input-inset">
		<label class="item-input-wrapper">
			<input type="search" ng-model="properties.workAbbr" placeholder="جستجو برای انتخاب مشاغل">
		</label>
		<button class="button icon icon-right ion-briefcase button-small button-energized"
			ng-click="getWorks(properties.workAbbr)">فهرست مشاغل و اشخاص حقوقی</button>
	</div>
</div>

but when I change ion-briefcase to ion-home it works fine and I don't know what is difference between these two icons. I think that, it is about icons are not installed correctly in my app.
Is it true? Thanks in advanced.