1. All appeals filed by the Plaintiff (Counterclaim Defendant) and the Defendant (Counterclaim Plaintiff) are dismissed.

2. The costs of appeal shall be borne respectively by each party.

The reasons for a member’s explanation on the instant case are as follows: (a) the fact that the price that the Plaintiff supplied to the Defendant does not exceed KRW 129,07,800; (b) the Defendant paid KRW 15 million to the Plaintiff on August 16, 2013; and (c) the Plaintiff and the Defendant agreed to deduct KRW 17,569,380, or KRW 19,023,640 from the price of the above teaching material on July 20, 2013; and (d) the testimony of the witness B of the trial court (including each number) and the testimony of the witness B, which are insufficient evidence to acknowledge that the Defendant requested the Plaintiff to return the original text of the teaching material in 2013, but the Defendant refused it, as well as the testimony of the witness B and D of the trial court, the reasoning of the judgment in the first instance as stated in the main sentence of Article 420 of the Civil Procedure Act.

Therefore, the judgment of the court of first instance is just, and the appeal of the plaintiff and the defendant is dismissed. It is so decided as per Disposition.