Text ( visual ) : unmediated Linguistic diversity in space and time / Johanna Nichols. -- Chicago : University of Chicago Press , c1992. -- xv, 358 p. : ill. ; 24 cm. -- Bibliography: p. 319-341 ; Includes indexes. -- ISBN 0226580563 ; (BA18180449) ; https://ci.nii.ac.jp/ncid/BA18180449 Author Heading(s): Nichols, Johanna. -- Classification(s): LCC : P143 ; DC20 : 417/.7 ; NDC8 : 801.09. -- Subject Heading(s): LCSH : Comparative linguistics ; LCSH : Areal linguistics ; LCSH : Language and languages -- Variation ; LCSH : Linguistic demography