Abstract. For a set of MHD equations for the solar atmosphere, Kumar et al. [1] have obtained a fifth degree polynomial in ω for the dispersion relation. On the other side, for the same set of equations, Dwivedi & Pandey [2,3], and Pandey & Dwivedi [4,5] have obtained a sixth degree polynomial in ω for the dispersion relation. Each of the two groups, tried to say that the results of the others are erroneous. Their main concern was that because of the difference in the degree of the polynomial, the roots in the two cases would be different and consequently, their results for the slow-mode and fast-mode magnetoacoustic waves were different. In fact, they obtained different results. Recently, Chandra et al. [6] have shown analytically that five roots of the two polynomials (fifth degree as well as sixth degree) are common and these roots pertain to the slow-mode and fast-mode magnetoacoustic waves. When the roots, pertaining to the slow-mode and fast-mode waves are common in the two polynomials, a good question arises why the two groups are getting different results and claiming that the results of the others are erroneous. In the present communication, we have reinvestigated the work and found that the results of Kumar et al. [1] are reliable. However, we could not ascertain the cause for the error in the results of Dwivedi & Pandey [2,3], and Pandey & Dwivedi [4,5].

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