Javascript 使用Angular.js ui路由器获取状态错误

我在尝试使用Angular.js导航路径时遇到以下错误

错误：

Error: Could not resolve 'principal.resourse.userrole' from state 'principal'
    at Object.t.transitionTo (angularuirouter.js:7)
    at Object.t.go (angularuirouter.js:7)
    at angularuirouter.js:7
    at angularjs.js:146
    at e (angularjs.js:43)
    at angularjs.js:45

我在下面解释我的代码

.state('principal',{
        url: '/principal',
        templateUrl: 'princpalview/princpal.html',
        controller: 'princpalHomeController'
    })
.state('princpal.resourse', {
        url: '/resourse',
        templateUrl: 'princpalview/res.html',
        controller: 'resPrincpalController'
    })
    .state('princpal.resourse.userrole', {
        url: '/userrole',
        templateUrl: 'princpalview/userrole.html',
        controller: 'resourcePrincpaluserroleController'
    })

princpal.html：

请帮助我解决此错误。

名称必须与princpal vs principal完全匹配-缺少一个“i”

<ul class="nav navbar-nav">
    <li ui-sref-active="active"><a ui-sref="princpal">Home</a></li>
    <li  ui-sref-active="active">
      <a ui-sref="principal.resourse.userrole" >Resource Management 
        <span class="caret"></span></a>
    </li>
</ul>

// state name
princpal.resourse.userrole
// ui-sref call
principal.resourse.userrole