public async Task <IActionResult> CreateAuthorCollection(IEnumerable <AuthorCreationDto> authors) { if (!authors.Any()) { return(NotFound()); } var authorsEntity = _mapper.Map <IEnumerable <Author> >(authors); _courseLibraryRepository.AddAuthorRange(authorsEntity); await _courseLibraryRepository.SaveAsync(); var authorCollectionToReturn = _mapper.Map <IEnumerable <AuthorDto> >(authorsEntity); var idsToReturn = string.Join(",", authorCollectionToReturn.Select(c => c.Id)); return(CreatedAtRoute( "GetAuthorCollection", new { authorIds = idsToReturn //authorIds = authorsEntity.Select(c => c.Id) //authorIds = from author in authorsEntity select author.Id }, authorCollectionToReturn)); }