public async Task <ICourseText> GetCourseTextByLARS(string LARSRef)
        {
            Throw.IfNull(LARSRef, nameof(LARSRef));

            CourseTextModel persisted = null;

            using (var client = _cosmosDbHelper.GetClient())
            {
                var docs = _cosmosDbHelper.GetCourseTextByLARS(client, _settings.CourseTextCollectionId, LARSRef);
                persisted = docs;
            }

            return(persisted);
        }