By representing a text by a set of words and their co-occurrences, one obtains a word-adjacency network being a reduced representation of a given language sample. In this paper, the possibility of using network representation to extract information about individual language styles of literary texts is studied. By determining selected quantitative characteristics of the networks and applying machine learning algorithms, it is possible to distinguish between texts of different authors. Within the studied set of texts, English and Polish, a properly rescaled weighted clustering coefficients and weighted degrees of only a few nodes in the word-adjacency networks are sufficient to obtain the authorship attribution accuracy over 90%. A correspondence between the text authorship and the word-adjacency network structure can therefore be found. The network representation allows to distinguish individual language styles by comparing the way the authors use particular words and punctuation marks. The presented approach can be viewed as a generalization of the authorship attribution methods based on simple lexical features.Additionally, other network parameters are studied, both local and global ones, for both the unweighted and weighted networks. Their potential to capture the writing style diversity is discussed; some differences between languages are observed. be simply derived or predicted solely from the properties of the system's individual elements. The existence of the emergent phenomena is often summarized with the phrases such as "more is different" or "the whole is something besides the parts".In this context, natural language is clearly a vivid instance of a complex system. Higher levels of its structure usually cannot be simply reduced to the sum of the elements involved. For example, phonemes or letters basically do not have any meaning, but the words consisting of them are references to specific objects and concepts. Likewise, knowing the meaning of separate words does not necessarily provide the understanding of a sentence composed of them, as a sentence can carry additional information, like an emotional load or a metaphorical message. Other features of natural language that are typical for complex systems have also been studied, for example long-range correlations [47], fractal and multifractal properties [5,10,13], self-organization [9,40] or lack of characteristic scale, which manifests itself in power laws such as the well-known Zipf's law or Heaps' law (the latter also referred to as the Herdan's law) [14,35,48].The network formalism has proven to be useful in studying and processing natural language. It allows to represent language on many levels of its structure -the linguistic networks can be constructed to reflect word co-occurrence, semantic similarity, grammatical relationships etc. It has a significant practical importance -the methods of analysis of graphs and networks have been employed in the natural language processing tasks, like keyword selection, document summarization, word-sense disambig...