The ongoing legal battle between Marvin Gaye's estate and Robin Thicke appears to be heading to trial. The late singer's children have filed a summary judgment over 'Blurred Lines' and claim to have audio proof that Thicke and producer Pharrell Williams have infringed on their father's song.

According to the Hollywood Reporter, the children have submitted an audio mash-up, which they believe shows "substantial similarities" between 'Blurred Lines' and Gaye's classic song 'Got to Give It Up.'

The counterclaim also includes statements allegedly made by Thicke and Williams admitting they were inspired by Gaye's song.

The summary judgement reads in part:

"Not only was it, therefore, Thicke and Williams who actually 'smelled money,' but it was they who then played the role of bully by suing Marvin Gaye's children when the Gaye children had the temerity to question why their father was not credited, or why 'Got to Give it Up' was not licensed, betting that the Gaye children would not have the will or resources to fight this battle. Thicke and Williams bet wrong, and they will now have to face the consequences of their misjudgment and their blatant copyright infringement."

As for the mash-up audio -- quite possibly the first time ever a mash-up is used in a copyright-infridgment case -- the recording of 'Blurred Lines' plays over the instrumental of 'Got to Give It Up' and vice versa.

"This material sounds like a perfect natural match because it blends sonically," reads the summary judgement.

The Gaye Family -- Nona Gaye, Frankie Gaye and Marvin Gaye III -- also have testimony from two expert musicologists who say that the songs have similarities in the vocal melodies, hooks, bass melodies, keyboards and percussion.

The summary judgment document also argues why Thicke's 'Love After War' should also be considered as infringement of Gaye's song 'After the Dance'

A jury trial has been scheduled for Feb. 10, 2015.

To read the Gaye Family's entire summary judgement memorandum, click here.