Ling

https://freeglobaluniversity.blogspot.com/search/label/VaticanKaabaStupaLinga

Lotus

www.dattatreyalotus.com

kuruvapur

https://www.google.com/search?q=kuruvapur

existed in all the four Yugas

Datta Tattva existed in all the four Yugas - Krita, Treta , Dwapar & Kali. Datta was the Guru of the Devatas. Even Sri Rama went looking for Datta. But only Atri and Anasuya were there. But on the day, Rama ascended the throne, Dattatreya came from nowhere, blessed Rama and Seeta and disappeared.
https://www.google.com/search?q=dattatreya+yugas

http://brahmasaraswati.blogspot.com/search/label/Yuga 

http://freeglobaluniversity.blogspot.com/search/label/Modes

http://harekrishnainfo.blogspot.com/search/label/YugaDharma

https://shivadurga.blogspot.com/search/label/Kedar