/// <summary>
        /// Deletes review request for given users on a pull request.
        /// </summary>
        /// <remarks>https://developer.github.com/v3/pulls/review_requests/#delete-a-review-request</remarks>
        /// <param name="owner">The owner of the repository</param>
        /// <param name="name">The name of the repository</param>
        /// <param name="number">The pull request review comment number</param>
        /// <param name="users">List of logins of users that will be not longer requested for review</param>
        public IObservable <Unit> Delete(string owner, string name, int number, PullRequestReviewRequest users)
        {
            Ensure.ArgumentNotNullOrEmptyString(owner, "owner");
            Ensure.ArgumentNotNullOrEmptyString(name, "name");
            Ensure.ArgumentNotNull(users, "users");

            return(_client.Delete(owner, name, number, users).ToObservable());
        }