The phrase "attested since" is correct and usable in written English.
It can be used to indicate that something has been confirmed or verified from a specific point in time onward.
Example: "The existence of the artifact has been attested since the early 19th century."
Alternatives: "documented since" or "verified since".
If we take the Latinate approach à la avuncular, then the Oxford English Dictionary provides materteral, attested since 1823 in humorous use, meaning "characteristic or typical of an aunt".
Evidence of competition between the landed aristocracy and the city-based middle classes in the political, economic and social spheres has been attested since the 11th century, but the scale of the conflict that erupted in 1341 was unprecedented.
This corruption of Vishnu to Vitthu could have been due to the tendency of Marathi and Kannada people to pronounce the Sanskrit (/ʃn/) as, attested since the 8th century.
There are several references to Hyrieus as the father of Orion that connect him to various places in Boeotia, including Hyria; this may well be the original story (although not the first attested), since Hyrieus is presumably the eponym of Hyria.
To this, I can attest, since my enlightened mother took me as a very small child to see him in Edinburgh and I remember the spectacular scene: of an adult managing to mesmerise adults by sheer talk, from a child's eye view, in the manner of the Pied Piper of Hamlin.
This is further attested to since the masonry of the birket is inferior in character and resembles the later Roman work in Syria.
Although the use of incendiary chemicals by the Byzantines has been attested to since the early 6th century, the actual substance known as Greek fire is believed to have been created in 673 and is attributed to an engineer from Syria, named Kallinikos.
West Semitic names started to be attested in Mari since the second kingdom era, and by the middle Bronze-Age, the west Semitic Amorite tribes became the majority of the pastoral groups in the middle Euphrates and Khabur valleys.
Plus, everyone knows--though not everyone admits--that angry sex is generally better, something both Coulter and I can attest to, since we've both dated liberals.
Po., Topics, and Porphyry's Isagoge were translated into Arabic; since they are lost (although attested in various ways), and since there is no mention of the translators, it is not easy to determine when they became available to the Arab readership; also from this viewpoint Gannagé (2012), 511 18 is an accurate and clear source of information.
Sydney argues that the rape was an "excess of love" and less severe than being deprived of love as attested by the line, "Since wanting is more woe than too much having".
