testimonial
US /ˌtes.təˈmoʊ.ni.əl/
UK /ˌtes.təˈmoʊ.ni.əl/

1.
testimonio, referencia, certificado
a formal statement testifying to someone's character and qualifications, or to the merits of a product, service, or claim
:
•
The website features several customer testimonials.
El sitio web presenta varios testimonios de clientes.
•
She received a glowing testimonial from her former employer.
Recibió un testimonio brillante de su antiguo empleador.