- Margarita, de Austria, Queen, consort of Philip III, King of Spain, 1584-16111
- Martyrdom1
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- Mary Magdalene, Saint1
- Mary, Blessed Virgin, Saint8
- Masnavis, Persian1
- Massachusetts--Wellesley7
- Massachusetts--Williamstown26
- Mathematical instruments1
- Mathematics2
- Maḥzor1
- Maḥzor. High Holidays1
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- Medicinal plants1
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- Medina Sidonia, Alonso Pérez de Guzmán, duque de, 1550-16191
- Medina Sidonia, Juan Alonso de Guzmán, Duque de, -15581
- Mediterranean Region1
- Memorial books (Holocaust)1