author: Anfumbom Kfutwah  Calixte Ida Penda  Josiane Warszawski  Georgette Guemkam  Mathurin Cyrille Tejiokem  Claire Rekacewicz  Pascal Boisier  Dominique Rousset 

https://journals.plos.org/plosone/article/file?id=10.1371/journal.pone.0021840&type=printable

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