na YOGYA-02090000025438 20090227023940.0 ind 010-020900000025438 615.853 615.853 Eld K ELDER, Mark Keamanan di air Mark Elder Cet. 1 Jakarta Sinar Harapan 1982 116 hlm ilus 21 cm Keamanan air YOPDYOG(B) 201206 3 06A0019213 06A0019214 06A0019215