Muhamad Fawwaz Akbar, Muhammad Itqan Mazdadi, Muliadi, Triando Hamonangan Saragih, and Friska Abadi, “Implementation of Information Gain Ratio and Particle Swarm Optimization in the Sentiment Analysis Classification of Covid-19 Vaccine Using Support Vector Machine”, j.electron.electromedical.eng.med.inform, vol. 5, no. 4, pp. 261-270, Sep. 2023.