Reading of prophets from a scroll or from a book

How should the prophets be read (in a synagogue after the Torah reading) — from a scroll, from a Pentateuch (with excerpts from the prophets) or from a TaNaCH (compendium of books of the Written Torah)?  

There are three halachic opinions on this issue:

• The opinion of the Levush and the Vilna Gaon is that it has to be read from a scroll written on a parchment according to all the laws of writing a Torah scroll.
• The opinion of the Magen Avraham and other later commentators is that one can be more lenient and use a printed book, since printing is like writing; material that is printed on paper is also kosher. However, he spoke about printing where a Jew would impress the printing plate upon paper by the force of his hand; only about such printing can one say that printing is like writing. According to this opinion, only complete books should be used, such as Joshua or Judges, etc. One has to pay attention to the fact that I Samuel and II Samuel are not complete books (rather, they’re two parts of one book).

However, today all of this is largely irrelevant, since today’s electronic printing methods certainly cannot be described by the phrase “printing is like writing”.

• The opinion of the Shulchan Oruch HaRav is that there is no need to read the prophets from a book, so the haftara can be read from a Pentateuch (with the weekly sections of the prophets).

It’s proper and preferable to obtain a scroll to read from. But, if this is not an option, one can read from whatever source is available. Some are careful to read from a complete book or from a complete TaNaCH. Others hold that if a scroll is not available, it makes no difference, where to read the prophets from.

Shulchan Oruch, section Orach Chaim, chapter 284, §1; Mishnah Berurah, ibid., subsection 1