@Book{Arp,
  Title                    = {Amorim, E; Andrade, C; Frederico, N; Umbelino, J}
  Title                    = {Los Cruceros turísticos en el Douro y el segmento de vinos e gastronomía: una propuesta de sustentabilidad sociocultural}
  Title                    = {nan}
  Title                    = {2012}
  Title                    = {Revista Estudios e Perspectivas en Turismo,}
  Title                    = {nan}
  Title                    = {nan}
  Title                    = {21}
  Title                    = {1050-1071 }
  Title                    = {nan}
  Title                    = {nan}
  Title                    = {nan}
  Title                    = {nan}
  Title                    = {nan}
  Title                    = {nan}
  Title                    = {nan}
  Title                    = {nan}
  Title                    = {nan}
  Title                    = {nan}
  Title                    = {nan}
  Title                    = {ttp://www.estudiosenturismo.com.ar/PDF/V21/N04/v21n4a14.pdf}
  Title                    = {nan}
  Title                    = {nan}
  Title                    = {nan}