Siagian, Valentine and Yuniwati, Ika and Rahman, Abdul and Lifchatullaillah, Endang and Inayah, Astrina Nur and Hasyim, Nurbayani and Dewi, Idah Kusuma and Mistriani, Nina and Simarmata, Janner (2020) Pengantar Kewirausahaan. Yayasan Kita Menulis, Medan.

Sari, Anggri Puspita and Anggraini, Dina Dewi and Sari, Marlynda Happy Nurmalita and Gandasari, Dyah and Siagian, Valentine and Septarini, Ri Sabti and Tjiptadi, Diena Dwidienawati and Sulaiman, Oris Krianto and Munsarif, Muhammad and Siregar, Prima Andreas and Nugraha, Nur Arif and Simarmata, Janner (2020) Kewirausahaan dan Bisnis Online. Yayasan Kita Menulis, Medan.