How can i fix this shelve?

I got this 2 foot floor shelve from someone i know that has a video store that is going out of business and the shelve is make out parallel wood and i have to replace 2 of the 5 shelve boards on it before i can any movies or games on it and i aint sure what i can use to fix the two shelve boards with since the shelve boards are also make from parallel wood also