public List <PresentationDto> Read()
        {
            try
            {
                var presentations            = _presentationRepository.Query().ToList();
                List <PresentationDto> psDto = new List <PresentationDto>();

                foreach (var p in presentations)
                {
                    p.Chapters = _chapterService.ReadByPresentationId(p.Id);
                    psDto.Add(p.ToPresentationDto());
                }

                return(psDto);
            }
            catch (Exception)
            {
                return(new List <PresentationDto>());;
            }
        }