Kochman A. Geochemical signatures of chert concretions and bedded cherts from the Kraków-Częstochowa Upland (Poland), the southeastern Franconian Alb, and the Bayerwald (Germany). agp [Internet]. 2026 Jun. 3 [cited 2026 Aug. 17];76(2):e75. Available from: https://wydawnictwo.pan.pl/index.php/agp/article/view/1210