Massenet & his letters = Massenet en toutes lettres : a new biography / by Anne Massenet ; translation by Mary Dibbern. (OCLC #870699448)

This volume’s title page includes a parallel title for only the title proper (“Massenet & his letters”), but not the other title information (“a new biography”). This situation is described in ISBD: When a prescribed source of information bears one or more parallel titles, but the statement of other title information is in only one language and script, the other title information, if given, is given
after the last parallel title transcribed.

    Title proper = Parallel title : other title information

For this title, that’s:

    Massenet & his letters = Massenet en toutes lettres :
        a new biography

Ўқиш китоби : эски ўзбек ёзуви намуналари, олий ўқув юртлари тил ва адабиёт факультеті студентлари учун кўлланма / тузувчилар: Т. Чермуҳамедов, Ф. Абдуллаев, П. Халилов.(OCLC #932769588)

This volume contains two books bound back-to-back, but as one is in Uzbek (which reads left-to-right) and the other is in Arabic (which reads right-to-left), they each get to have their front cover.

I’ve described this as dos-à-dos binding (“back-to-back”) in a note, which may not be precise, as such books typically have alphabets that read the same direction, so require a third board as a shared back-cover between them, and end up with more of a Z shape.

In structure, this is also similar to a tête-bêche binding (“head-to-tail”), which has two front covers, but has one volume flipped 180 degrees to accomplish this. As these two books really are back-to-back (and because tête-bêche binding is sometimes also called “dos-à-dos”), that term seemed more accurate/clear:

    500 __ ǂa Dos-a-dos.