Website 'TMZ' obtained Juan Gabriel's death certificate, who died on August 28 in Santa Monica, California.
According to the document, the singer's history of pneumonia was among several significant factors that contributed his death.
The death certificate confirmed the Mexican singer-songwriter's death was caused by arteriosclerotic cardiovascular disease, which prevents blood flow to the heart.
The document also lists diabetes and hypertension as factors.
In April 2014, 'El Divo de Juárez' was hospitalized in Las Vegas due to pneumonia and had to cancel numerous shows in California.