@using Microsoft.AspNet.Identity
@if (Request.IsAuthenticated)
{
    using (Html.BeginForm("SignOut", "Account", FormMethod.Post, new { id = "logoutForm", @class = "navbar-right" }))
    {
    <ul class="navbar-nav mr-auto">        
        <li class="nav-item">
            <a class="nav-link" href="javascript:document.getElementById('logoutForm').submit()">UITLOGGEN</a>
        </li>
    </ul>
    }
}