**MATHEMATICS** | | |

Branislav Z. Popović Boško S. Jovanović | Some convergence rate estimates for finite difference schemes - interpolation technique_{ }_{ } | 7 |

John O. Adeniran | On certain anticommutative algebras II | 17 |

Nikola Rosić | Double transformation and equation *L*_{n}[*a*_{0}, *y*] | 25 |

Sever S. Dragomir Valentin M. Boldea | Some new remarks on Cauchy-Buniakowsky-Schwarz's inequality . | 33 |

M. O. Ojo | Analysis of bioassay data with more then one type of stimulus and measurement of potency when the responses are quantal | 41 |

James A. Oguntuase | Remark on some integral inequalities for convex functions . | 49 |

J. A. Oguntuase Raman Adegoke | Weighted norm inequality for some integral operators | 55 |

S. A. Akinleye A. R. T. Solarin | On production planning problems with non-linear cost function | 63 |

Mirko Lepović | On caconical graphs and eigenvectors of graphs | 75 |

Zdravko F. Starc | Finding the boundary curves of the second order linear ordinary differential equation | 87 |

Alfred A. Akinsete | Blocked finite tandem queues with withdrawals and feedback | 93 |

Dragan Stevanović Ivan Gutman | Hosoya polynomials of trees with up to 10 vertices | 111 |

**PHYSICS** | | |

Ljubisav Novaković | The expansion mechanism and a recession of galactic clusters | 121 |

Branko B. Obrović Slobodan R. Savić | Moment equation of ionized gas in the case of changeable electroinductivity . | 151 |

**CHEMISTRY** | | |

Ranđel Mihajlović Dragić Banković Mirjana Vukićević | Content of lead in the soil and plant material at the highway, section Smederevo-Batočina | 157 |

**BIOLOGY** | | |

M. I. Lesovskaya | The erithropoetic effects of tryptophan and its metabolites | 163 |