In Poland, all the issues related to copyright law are regulated by the Act on Copyright and Related Rights of February 4,1994, as amended. According to this act the work, which has been already disseminated, may be copied without author's permission but only for the purposes of private use, i.e. study, research, review.
This means that a single copy of a part or even an entire document can be made, but only for the purpose of private use.
If more than a few words from another author's work are cited for research and teaching purposes, for all the quotations or paraphrases the proper in-text citations as well as references at the end of the paper should always be provided.